What is tanking?:
Any MMO player will know the role of the "Tank" but the word's usage in EVE Online is a little different. Broadly speaking, a tank is whatever you use to keep yourself alive and it's something every ship can do. The MMO holy trinity of tank, healer and damage-dealer are combined into every ship in EVE. Because of this ability to self-heal, the word "tank" in EVE generally refers to the combination of both resisting damage and healing it. Fitting your ship then becomes a matter of balancing between tank and damage.
Read on to find out how to select what type of tank to use and learn all about armour tanking.
When is tanking used?:
While tanking is relevant to all aspects of EVE that involve combat, its usefulness in PvP is somewhat limited. Once fleets begin to get above a certain size, their concentrated fire will blast almost any ship apart in short order regardless of how strong its tank is. With this in mind, it becomes clear that setting up your tank effectively is most important in missions, complexes and deep space asteroid belts. Since NPCs tend to deal a lot less damage than players, a well-designed tank can handle them reliably.
Differences between shield and armour:
While on the surface shield and armour may both seem like simple hitpoint buffers, they work very differently. Shield recharges slowly over time like your capacitor but damage to armour must always be repaired manually. If your shield drops below 25% hitpoints, extra damage can leak through and hit your armour but damage cannot leak through your armour and hit your hull.
Selecting your tank type:
Trying to tank both shield and armour is a waste of valuable slots and will cripple your ship's combat effectiveness so it's best to choose only one type. When choosing which type of tank to use, you can usually find out which would be most effective by examining your ship's slot layout. Since shield modules go in mid slots, ships with more mid slots than low slots make better shield tankers. Similarly, armour modules go in low slots so those with more low slots make better armour tankers. As a general guideline, Gallente and Amarr ships are best armour tanked, Caldari are best shield tanked and Minmatar have ships that can handle either comfortably. If in doubt, ask a few older players which type of tank should go on your ship.
One final small consideration is that each slot used for shield or armour modules could be used for alternative modules if you chose the other type of tank. Rather than being filled with shield modules, mid slots can be used for capacitor rechargers and important PvP modules like warp disruptors, microwarpdrives and electronic warfare modules. Similarly, low slots can be used for damage-enhancers, power diagnostic systems and various hull upgrades. This usually isn't the deciding factor in which type to choose but sometimes comes into play in fleet PvP setups.
Continue to part 2, where I discuss armour tanking in detail.