First, some basics. There are three main weapon types in Eve - turrets, missiles and drones. Turrets can be further divided into projectiles, hybrids, and energy weapons. In addition to these 'major' weapon systems, Eve features two forms of area-of-effect weapon - bombs and smartbombs - and one direct damage weapon, the doomsday device.
All weapon systems other than bombs and doomsdays are available in a range of sizes, from small (corresponding to frigate sized hulls) to XL (designed for use on capitals). Smartbombs are slightly different, ranging from micro (a size down from small), to large (i.e. battleship sized). Other than on a few specialised hulls, fitting larger weapons than is normal for your class is generally prevented by the greater fitting requirements. However, there is nothing to stop a ship from mounting smaller weapons than intended.
Turrets are the most common weapon system that you'll encounter in PVP, and are the standard against which all other options are measured. Their potential damage output is generally very good, but is highly dependent on circumstances. As a result, their real damage output relies more on your ability to control the engagement than would be the case with other weapon systems.
Damage from turrets is not constant - an element of chance is involved both in determining whether you hit in the first place, and how much damage that hit deals. The likelihood of landing a hit as well as the quality of that hit are determined by two factors - tracking and range.
Tracking is a measure of how good a turret is at hitting moving targets. To explain this, we need to briefly mention angular velocity. Imagine that someone is running in circles around you, and you have to keep your arm pointed at them all the time - the speed at which you have to rotate your arm indicates their angular velocity relative to you. Consider that if that person were quite far away, you would only have move your arm slowly. However if they were right next to you you would need to move your arm very quickly, even if they were only walking around you relatively slowly. The higher the angular velocity between you and your target, the less likely your turret is to hit them and the less damage it will hit for if it does. The target's signature radius (effectively the size of their ship) also plays a factor - smaller targets are harder to track, while larger targets are easier to track.
When a target has low angular velocity, turrets can usually hit quite reliably for excellent damage; a large turret can hit even the smallest target for its full damage providing its angular velocity is low enough*. However as the target's angular velocity increases, a turret's hit chance and damage output can decrease dramatically. The turret's tracking speed (which varies from weapon to weapon) and signature resolution (which is fixed based on the size of the gun, with smaller guns having a lower signature resolution) determine how effective it is at keeping track of such a target - a turret with a high tracking speed and a low signature resolution will probably deal strong damage to even the most evasive target, while a turret with a low tracking speed and a high signature resolution may be unable to hit at all unless its target is almost stationary.
To be clear, we're talking about angular velocity here not speed - a target can be moving very quickly, but if they don't have any angular motion relative to you then it won't affect your turrets' performance. Similarly, it's important to remember that angular velocity is relative - your target might be completely stationary, but if you are orbiting them then that will give them angular velocity relative to your ship, and thus reduce your chance to hit them just the same as it would if the situation were the other way around.
The second thing to consider with turrets is range - like tracking, this is made up of two components - optimal range is the distance outside which your hit chance and damage naturally begins to degrade (inside this distance range has no effect - there is no such thing as being 'too close' other than the fact that closer targets generally have higher angular velocity). Accuracy falloff tells you how quickly your damage output will degrade once outside optimal range. For example, a turret with a long optimal range but a short accuracy falloff can hit out with its full power at quite a distance, but quickly becomes less effective if its target moves outside of that range. On the other hand a turret with a short optimal range but a long accuracy falloff would have to be very close to deal its full damage, but can afford to be quite flexible when it comes to sticking within that range, and will still have a reasonable chance to hit some way outside of it.
For more detailed information on turret mechanics, see my post on signature resolution and my tracking & spiralling video.
With these factors in mind, let's have a look at the three varieties of turret available to us:
* The exception to this rule is XL (i.e. capital) sized turrets when fitted on titans, which also receive a direct damage reduction based on signature radius. This was introduced recently to curb the use of large supercapital fleets against subcapital targets.
Associated race: Minmatar
Variants: Autocannons (close range), Artillery (long range)
Advantages: No cap use, selectable damage type, easy fitting (autocannons), high volley damage (artillery), long accuracy falloff
Disadvantages: Relatively low dps, difficult fitting (artillery), long reload time, short optimal range
Projectiles are one of the most popular turret choices for PVP, and projectile bonuses are generally found on minmatar ships. Projectiles have a couple of distinct advantages over the other turrets: Firstly, projectiles are the only turrets which do not use capacitor to fire, meaning that providing you still have ammo you can keep shooting things without having to worry about your cap levels. Second, projectiles have some limited ability to choose the damage type they put out - while all t2 projectile ammo types deal a mix of explosive and kinetic, their t1 and faction ammo comes in a variety of flavours. The three most common damage types for close range (fusion, phased plasma, and emp) deal mainly explosive, mainly thermal, and mainly EM damage respectively. However, projectile turrets have a slow reload time of 10 seconds which makes switching damage type mid-fight a time consuming exercise.
Autocannons are the close range variant of projectile turrets. They have the shortest optimal range of any turret (typically only a couple of km), however long accuracy falloffs make them very flexible and allow them to perform well outside of this range. This long falloff range can be enhanced by t2 barrage ammo, which provides a large bonus to falloff. As a result, autocannons can continue to hit for reduced damage even at ranges where pulse lasers and blasters would no longer hit at all. The maximum damage output of autocannons is similar to pulses and less than blasters, however since their optimal range is so short they will only put out their full damage at very close range, with damage output gradually decreasing the further they are from their target. While some brawling ships might use autocannons in or close to their optimal range, the majority of the time they tend to be used outside of it - this means that autocannons actually end up having the lowest damage output of the close range turrets in common usage, although this is mitigated to an extent by the fact that they can choose their damage type to match an opponent's weaker resists, and by the fact that many minmatar hulls receive multiple damage or rate of fire bonuses.
An often overlooked advantage of autocannons is that they consume far less powergrid than the other close range turrets. Since many minmatar ships are designed to be able to fit either autocannons or artillery (the latter being far more grid hungry), this often means that autocannon setups are easier to fit with a reasonable tank than the equivalent ships of other races. It's not uncommon for non-minmatar ships to fit autocannons in order to free up grid (and capacitor) for their tank, especially if that ship doesn't receive a damage bonus to its racial weapon system. Thanks to their long accuracy falloff, autocannons benefit significantly from any module or ship hull that increases projectile falloff range. Since their optimal range is so short, changing ammo has almost no effect on the range of autocannons with the exception of t2 ammo, and for this reason there is little reason to use anything other than faction/t1 high damage ammo (phased plasma, fusion, emp) and t2 barrage (t2 hail is not a popular choice since it reduces falloff significantly).
Artillery are the long range variant of projectile turrets. These have a moderate optimal range, but continue to have the long falloff range offered by autocannons. Since t1 ammunition only affects optimal range (not falloff), this accuracy falloff makes close range artillery boats particularly flexible, while being less beneficial at sniping ranges. Probably the most significant thing about artillery is their high volley damage - while they fire slowly, each hit does a very large amount of damage compared to other weapon systems. While this doesn't give artillery higher dps overall, it does allow groups of artillery fit ships to 'alpha' a target, destroying it a single shot and thus circumventing any active tank or remote repair that it might have. Unlike autocannons, artillery comsume large amounts of powergrid to fit - many minmatar ships can't fit a full rack of the highest calibre artillery without using fitting mods, and that's without a tank! With more optimal range artillery benefits much more than autocannons from ammo switching, particularly as a result of the mid-range ammos (titanium sabot and depleted uranium) which boost both range and tracking at the expense of some damage output - while not used as standard, this can come in particularly handy when trying to hit small ships. In small gang PVP artillery are quite often used with close range ammo, where they rely on their long falloff for flexibility and maximise the power of their alpha strike.
Associated race: Gallente, Caldari
Variants: Blasters (close range), Railguns (long range)
Advantages: High dps (blasters), good tracking (blasters), long range (rails)
Disadvantages: Short range (blasters)
The two variants of hybrid turret have relatively little in common. Hybrid turrets use both ammunition and capacitor to fire, although they require significantly less capacitor than energy turrets. Unlike projectiles they're fairly locked into their damage types, with all hybrid ammo dealing a mix of kinetic and thermal damage in some form or other (the t2 ammos tend to deal more thermal, while t1 and faction ammo puts out kinetic as the majority). In their favour, hybrid turrets take only 5 seconds to reload rather than 10, allowing hybrid ships to adjust more quickly to changes in range than their projectile counterparts.
Blasters are the close range hybrid turrets, and are the highest damaging weapon system around. These weapons are designed for close range brawling - they have both short optimals and short accuracy falloffs, but make up for that in damage output and tracking speed. A ship fitting blasters needs to be confident that it can get into range of its opponent, but if it's able to do so it can be truly devastating. Blaster ships tend to require good speed and good range control as a result, with scrams and webs being the order of the day. Blasters are particularly popular on gallente ships, but can work equally well on the caldari hybrid platforms. As you'd expect from such a close range weapon system, blasters significantly out-track both autocannons and pulses, particularly on ships with a built in tracking bonus (of which the Gallente have quite a few).
Railguns are the hybrids' long range variant, and could hardly be more different to their close range counterparts. Railguns have the longest range of any weapon system in eve, generally far in excess of the other long range variants. To offset this they have relatively short accuracy falloffs (not that they ever have to fight in falloff) and only moderate dps with fairly low damage per shot. The long range of railguns is less beneficial than it once was, since the ability of combat probes to quickly provide a warpin has made the difference between a distant target and a very distant target largely irrelevant. Still, railguns remain a good choice for the long ranged sniper and are equally apt for mid-range kiting when loaded with close range ammo. With long optimal ranges, railguns benefit greatly from hulls or modules which increase optimal range (which most caldari hybrid hulls do).
Associated race: Amarr
Variants: Pulse Lasers (close range), Beam Lasers (long range)
Advantages: Long optimal range (pulses, compared to other close range weapons), high dps (beams, compared to other long range weapons), effectively no ammo consumption, instant ammo switching
Disadvantages: High cap consumption, poor tracking (pulses, compared to other close range weapons)
Energy turrets continue the trend seen between the previous two weapon systems; they consume large amounts of capacitor to fire, but a single round of ammunition will last indefinitely (faction and t2 crystals will eventually break after firing thoudsands of shots, while t1 crystals will quite literally last forever). In addition, energy turrets are able to switch ammo instantaneously, adjusting range much more quickly than either of their counterparts. Like hybrids, energy turrets are locked into dealing fixed damage types - in this case a mix of EM and thermal, with the proportion of thermal damage decreasing as longer ranged crystals are used. This is less of a handicap than it might initially seem, given current the popularity of shield tanking in PVP.
Pulse lasers excel as a mid range weapon system - they have long optimal ranges and short accuracy falloffs, with their t2 scorch ammo providing a massive boost to optimal range. This gives pulse lasers a very similar effective range to the equivalent sized autocannons, however since they're almost always fighting within their own optimal range pulse lasers are able to deal close to their maximum damage output all across their range bracket - something which autocannons cannot to. For this reason, pulse lasers are the premier weapon system for fighting at medium ranges (up to around 20km on frigates, out to 50km or more on battleships). I'll state that one more time since it's so often overlooked - at medium ranges, pulse lasers will have a much higher actual damage output than autocannons despite having similar 'on paper' dps. In addition, the fact that they lose no time to reloading makes pulse lasers very versatile - they can switch instantaneously between close range faction multifrequency and long ranged scorch crystals, making them a very versatile weapon system.
The main downside of pulse lasers is their reliance on capacitor - this makes their users highly vulnerable to neuting as well as competing for juice with other cap-intensive modules frequently found on a close to mid range ship, including MWDs for kiting, active tanks, and neuts of their own. For this reason, many such ships fit a cap booster to ensure that they can keep everything running even while under duress (this applies more to pulses than beams, since beam ships are generally not inside neut range and are less reliant on other cap-intensive modules). Just as autocannons benefit greatly from falloff bonuses, pulse lasers are incredibly powerful by boosted by hulls and modules which increase optimal range. While their tracking isn't terrible, pulse lasers also track more slowly than other close range weapon systems and tracking bonuses (or webs) on Amarr ships are relatively rare. Because of this, pulse lasers can have difficulty tracking targets at very close range.
Beam lasers are less common than their close range counterparts, partly because the excellent mid range performance of pulses makes close range beams pretty much obsolete - they have similar range and damage output to pulses with scorch, but with much worse tracking and without the ability to go any closer if caught in an undesirable situation. Where beams do see use is as long ranged sniping weapons, particularly the battleship sized tachyon beam lasers - a very heavy hitting variant which is nototiously hard to fit. Beam lasers tend to outdamage the other long ranged weapon systems, although they have neither them impressive range of railguns nor the high volley damage of artillery. Aside from tachyons which feature quite regularly on sniping battleships and 3rd tier battlecruisers, beam lasers tend to be quite rare in PVP compared to the other long ranged weapon systems.
Associated race: Caldari
Variants: Rockets, Assault Missiles, Torpedoes (close range), Light Missiles, Heavy Missiles, Cruise Missiles (long range)
Advantages: Long range (all long range variants), selectable damage types, no tracking
Disadvantages: Relatively low dps, long reload time, delayed damage
Missiles are a highly versatile weapon system. Like projectile turrets they can choose their damage type, although some hulls come with a bonus to a specific flavour (typically kinetic on caldari missile boats). They also share the 10 second reload time associated with projectile turrets as well as the lack of a capacitor requirement to fire them. That however is really where the similarities to turrets end.
The mechanics of missile damage are very different to those of turrets. In many ways, they are simpler; there is no chance based element to missiles, they simply have a set amount of damage which they will deal with each hit. This damage can be reduced by two factors - the target's size and the target's speed (in any direction). If a target is moving more quickly than the missile is designed for (known as its explosion velocity), the missile will do less damage. If the target is smaller (in signature radius terms) than the missile is designed for (in this case known as it's explosion radius), the missile will also do less damage. Simple, right? It does get slightly more complex - a target which is moving faster than the missile's explosion velocity can still be hit for full damage, providing its signature radius is larger than the missile's explosion radius (for example due to being target painted, or due to running a MWD). This doesn't work the other way round - a smaller target will take reduced damage no matter how slowly it's moving.
Given all this, it's fairly simple to get missiles putting out their absolute maximum dps - you simply need to be shooting a target the same size or larger than your missiles are designed for, and ideally they should be webbed. The fact that there's no chance based component makes missile damage very consistent, although in general they don't have quite the same damage potential as turrets (due to the consistency however, the numbers are much closer than tools like EFT would suggest). Since they don't haven to worry about tracking, missiles will remain effective no matter how close their target is. They do have a maximum range, which can be worked out as roughly their missile velocity multiplied by their flight time (this gets a little more complex when your target is moving - they might appear to be in range when you fire, but your missile needs to travel to the place where they are at the end of its flight, not the beginning). It's even possible for a ship to outrun missiles entirely, although this generally required a very small ship and very large missiles, which would probably do very little damage anyway.
Missiles come in both short ranged variants (rockets, assault missiles, and torpedos) and long ranged variants (light missiles, heavy missiles, and cruise missiles), covering small, medium, and large ships respectively. There are also citadel torps and citadel cruise missiles, which are XL weapons for use on dreadnaughts and titans. The close range variants deal more damage, but have far more restrictive ranges than their long ranged counterparts (rockets hit out to around 10km with good skills, while torpedos and assaults reach out to around 20km. They generally also have larger explosion radii and lower explosion velocities, making them less effective against smaller targets (this is less true for rockets which remain very effective as an anti-frigate weapon, but is particularly true in the case of torpedoes). The long ranged variants on the other hand have excellent damage projection, especially when you consider that there is no reduction in damage as range increases. This is exacerbated on those caldari hulls which have a missile velocity bonus (which is quite a few of them), giving missiles one of the best range and damage combinations of any weapon system.
Missiles do have their downsides. Firstly, the damage from missiles is not immediate - they need to travel to their target first. This makes missiles less popular in many large fleets, where targets can often be destroyed before your missiles have even landed. Additionally while missiles are excellent against similar sized or larger targets, they generally perform quite poorly against targets smaller than their design specs unless those targets are heavily webbed and/or target painted.
There are a couple of unusual missile types which can be loaded into regular launchers - F.O.F missiles and defender missiles. Neither of these are really that useful outside of very specific circumstances, but we'll talk about them briefly. F.O.F missiles will automatically attack a nearby hostile target without you needing to lock them - this can allow missile ships to continue fighting even when jammed by ECM. Unfortunately you have no control over which target F.O.F missiles attack, and once you've waited out the 10 second reload time to switch to them it's likely that the jam cycle will already be over. F.O.Fs are rarely carried in PVP, and are really only useful if you're going into a fight where you expect to be jammed regularly (and ideally where you're going to be fighting a small number of targets so that you can reasonably predict who your missiles will be shooting). Defender missiles are also automatic, however these are designed as an anti-missile system - they will attempt to shoot down any other missiles currently in flight for which your ship is the intended target. Because defenders only attack missiles heading for you personally and not your fleetmates they're of fairly limited use, especially since you can't fire regular missiles while they're loaded. The one situation where defender missiles can be useful is on a tackle interceptor, where they can help reduce incoming missile damage while you wait for your gang to arrive and back you up.
Associated race: Gallente, but all races to an extent
Variants: Combat Drones (mobile, short range), Sentry Drones (stationary, long range), Electronic Warfare/Utility Drones (no damage output, instead providing EWAR or other effects), Fighters/Fighter Bombers (capital)
Advantages: Selectable damage types, tracking independent of user, no capacitor consumption, can carry multiple sizes
Disadvantages: Delayed damage (combat drones), can be destroyed, fairly low damage unless supported by another weapon system
Drones are featured on most ships of cruiser size or above, and even some frigates. For this reason, training drone skills is essential regardless of the race of ships that you choose to fly. Only a small number of ships use drones as their primary weapon system (most of them Gallente), and even then they are usually combined with a regular high slot based weapon system in order to round out the ship's damage output.
Drones are small independent ships which you can control remotely - you can issue orders to attack a target or to return and orbit your ship, as well as being able to launch and retrieve flights. When you tell a drone to attack something it will fly over to it, orbit, and start shooting until the target either gets out of range (in which case it'll fly over to it again and carry on), dies, or you order the drone to return. Other than carriers* no ship can operate more than five drones at a time, although you can potentially carry more in your drone bay. The number of drones you're able to operate or carry at a single time is limited by you ship's drone bandwidth and drone bay, in mbit/sec and m3 respectively (all drones have identical values for both, so the different units are really just cosmetic) - larger drones take up more capacity, while smaller drones take up less.
To order your drones to attack a target you'll need to have them locked, and they will need to be within your drone control radius (a range which starts at 20km and increases based on your drone skills). However should you lose lock or the target should get further away, your drones will happily continue attacking them - in fact depending on your settings (which can be modified in the drone settings window), your drones can even be set to respond to any hostile that attacks you without being ordered to do so. This makes drone ships very resistant weapon to ECM - if you can set your drones to attack the ECM ship before they jam you, there's a good chance that you'll be able to drive them off.
When it comes to applying damage, drones follow the same mechanics as turrets (with the exception of fighter bombers, which use missile mechanics). That means they have optimal ranges, tracking speeds, the lot. The big difference is that since the turrets are mounted on the drone, you don't need to worry about your ship being in range or targets getting under your guns - as long as your drones can catch them it's not a problem. This makes drones an excellent defence against small ships which your main guns might otherwise struggle to hit.
Unfortunately drones aren't particularly intelligent - they'll orbit a target and shoot it but don't really have any more finesse than that. A heavy drone (which has worse tracking than the smaller drones) will happily orbit a small target too close to track it, and due to the way drones slow down once they get into orbit range they can have real trouble keeping up with fast-moving targets even if the drone is technically fast enough to do so. The fact that drones have to travel to get in range of a target before they can begin shooting is also a drawback, particularly in large fights where your drones will spend a lot of time travelling between targets. It also gives you the potential to lose your drones if you're forced to warp out of a fight before you're able to recall them.
When it comes to choosing your drones, you should consider the kind of targets that you intend to use them against. If you're mainly carrying drones as an anti-frigate defence then light drones (particularly warrior IIs which have the highest top speed) are a good idea. If you're planning to use your drones as your primary weapon system against larger targets, heavy or medium drones will be preferable. Each size of drone has a variation for every damage type, however unless you have a very good reason to do otherwise it's usually best to use either thermal drones (which have the highest base damage) or explosive (which are the fastest). If possible you should always try to field the maximum number of drones, even if that means using a smaller size - you'll get more damage from five light drones for example than you would from three mediums. One interesting point to note is that you can actually assign your drones to a fleet member (usually a fast locking frigate) and they will automatically attack any target which that ship engages. Unlike fighters (mentioned below) the assigned pilot doesn't get full control of the drones and they don't replace any drones of their own.
In addition to regular combat drones, there are a few types of specialised drone which perform in a different way:
These have equivalent firepower to heavy combat drones, but instead than chasing down a target sentry drones are immobile and attack from range. Some sentry drones can hit out further than others, with anything from 30-100km being relatively normal depending on skills and associated modules. Sentry drones offer good damage for a mid-to-long range weapon system, and unlike regular drones you don't need to worry about travel time - their damage is immediate. On the other hand, sentry drones do lose some of the flexibility associated with regular drones: Firstly they can't move, which means you cannot recall them unless you fly back to the position where you dropped them (or remain stationary while they're in use). Secondly, the tracking of sentry drones is relatively poor (in the same ballpark as large turrets, with the longer ranged drones tracking significantly worse than the close ranged ones). Because of this, sentry drones are much less effective than other drones for fighting up close and personal and generally won't help you hit targets which have got under your guns. It is worth noting however that if you move away from your drones after launching them, they should still be able to hit targets which your ship itself might not (and vice versa).
Electronic Warfare & Utility Drones
In addition to damage drones there are also a range of ultility drones offering effects such as electronic warfare, mining, or remote repair. Like modules, drones are stackling penalised against each other and this makes many of the electronic warfare drones fairly ineffective. ECM drones however are something of an exception - since ECM is pure yes/no mechanic these drones don't become any less effective as you pile more of them onto a target, and despite their low individual jam strength a flight of light ECM drones can have a fairly good chance to getting a jam, particularly against smaller targets.
While much less popular than ECM drones, there are two other drone variants which see fairly frequent use. Remote repair drones (either the armour or shield variants) are a fairly common choice for logistics ships since they increase their ability to repair friendlies and saves the logi pilot from having to lock up both hostile and friendly ships at the same time (which can have embarrassing results). The repair amount from these drones is significantly lower than regular remote repair modules, however en masse they can be fairly effective. The other option which is sometimes used are the recently added stasis webifier drones - while these much less effective than actual webs and suffer from the same stacking penalties as other ewar drones, one or two webber drones can make it that much easier to land tackle on a ship that might ordinarily be slightly faster than yourself.
Fighters (and fighter bombers) are a specialised class of drone only usable by carriers and supercarriers. These are much larger and more powerful than regular drones, however the unusual thing about them is that they're capable of warping. In fact if their targets warp off, fighters are able to follow them anywhere in the solar system! In addition to that, it's possible to assign your launched fighters to any fleetmate in the system who can then control them as if they were their own drones (they're still only able to field five drones at a time though, so won't be able to use their own drones while they're controlling a flight of fighters). This makes fighters very popular for ratting, where they can be assigned to support your ratting ship while the carrier remains just outside the shields of a friendly POS.
* And the guardian vexor, but since only a couple of those still exist and you'll never see one it's effectively just carriers.
Smartbombs are an area of effect weapon system, and in truth there's nothing smart about them. A smartbomb deals a set amount of damage to every ship within a certain distance of the user, regardless of whether they are friendly or hostile. Smartbombs are most commonly seen on battleships and capital ships, where large smartbombs can be used to clear drones, or (if the user fits a whole rack of them) to destroy frigate gangs. Large groups of battleships with smartbombs can actually be used to destroy gangs of relatively tough ships such as battlecruisers and HACs - a particularly popular way of doing this is to drop a gang of them using a titan bridge directly onto a hostile gang.
It's a common misconception that a battleship with one or two smartbombs is highly dangerous to frigates, and that's not really true - a large smartbomb does 300 damage every 10 seconds, meaning a frigate would need to sit there for almost a minute before it's likely to be in any danger (or longer if it's tanked). Where smartbombs are dangerous is when a ship fits a while rack of them, in which case they can easily be avoided by orbiting outside of their effective range: 5km for a large smartbomb, or 6km if they're using t2 (which is less common than you'd expect due to fitting requirements).
Bombs are a weapon system which is unique to stealth bombers. They're an area of effect weapon that works almost like a cross between smartbombs and missiles. When the launcher is activated, the bomb flies directly forwards for 10 seconds, during which time it will travel 30km. After that it explodes, dealing damage to everything within 15km of its impact point.
Like missiles, the damage causes by bombs is reduced by signature radius - a smaller target will take significantly less damage from a bomb than a larger one. Unlike missiles however, the speed a ship is travelling at has no effect. In general you're unlikely to be killed by a single bomb unless you have a very high signature radius and very little tank (such as a frigate or destroyer with its MWD turned on). While people keep insisting on trying it, bombing as a solo activity is generally not effective for this reason. Coordinated groups of bombers on the other hand are much more dangerous, and can wipe out gangs if done effectively. Bombs will also destroy each other if caught in the blast, although they are resistant to damage of their own type - up to 6 bombs of the same type can be launched together without destroying each other (more than that requires some creative positioning to make sure the explosions don't overlap).
While it's traditional to fit weapons in your high slots, there are a few strong alternatives. First and foremost of these are the cap warfare modules - energy neutralizers and nosferatu. Energy neuts drain your opponent's capacitor, although they also require some of your own capacitor to operate. Nosferatu drain a smaller amount of capacitor but give it straight to you instead, with the caveat that they will only have an effect if your opponent's overall capacitor percentage is higher than yours.
While they sound similar, these two modules are used in very different ways. Neuts are generally used as a defence against smaller targets (a frigate or cruiser hit by an oversized neut will be capped out very quickly) as well as making a good weapon against active tanked ships. Nos on the other hand aren't particularly effective for capping your opponent out but are great for keeping your own ship topped up on juice, particularly if you're running an active tank or other cap-intensive modules.
While neither of these modules directly damage your opponent, the utility that they offer makes them a very popular choice. It's usually not a good idea to give up any of your primary weapon system to fit these, however if you have any spare high slots (as most minmatar ships do) or if you're looking to replace your secondary weapon system (such as the turrets slots on a drone boat), a bit of cap warfare can come in very handy!
This is a direct damage weapon that can only be used on titans. It deals a fixed two to three million damage regardless of tracking or signature radius, however it can only be used against other capital ships. If you need more information than that, you're probably not at the level that this guide is aimed for!