Above all else, EVE is a game of information. Whether it’s having good knowledge of the game’s various ships and what they do so you can prioritize targets in a small gang fight, or getting word from a spy that an enemy alliance is about to collapse into civil war so you can strike at their space while they’re weak, having the facts and knowing how to use them is very important.
One of these avenues of information is scouts. Any alliance worth their salt had an extensive network of scouts in covert ops ships to do reconnaissance for fleets and scout enemy systems for structures or strategic assets like towers or moons.
Having a scout in a fleet to provide intel to the fleet commander about what is in the systems ahead is invaluable. They can report on upcoming gatecamps to make sure the fleet stays safe until it gets to where it needs to be, or they can use scanning probes
to track down hostiles and provide a warp-in point for the fleet. FC’s who are really dedicated to their job will roll a scouting alt on a separate account and control both characters at once. If a scout isn't doing recon for a specific fleet or op, he can scout out home or staging systems so that the alliance knows what their enemies are doing at all times.
Moons in EVE don’t show what materials, if any, can be extracted from them. Players have to probe
these moons for that information, and it isn’t retained by the game client, so it needs to be recorded. ‘Money moon’ is the term for any moon that can be harvested from to turn a worthwhile profit. Finding these moons is very important, since processing and selling moongoo is what currently keeps most nullsec alliances up and running. Along with probing moons, scouts also scan for enemy towers, marking down which ones are important or worth attacking. Towers that mine valuable moon minerals, or have cynojammers installed are important to know about.
While not an act of information gathering like the first two, a third way that scouts help an alliance is by providing cynos for capital ships to jump to. Certain types of capital ship are too big to use regular jump gates, but have the engines to jump themselves, so they need other ships to act as beacons to jump to by using a specific ship module called a Cynosaural Field Generator
A Cynosaural Field
Titans can also create a jump bridge between themselves and the cyno beacon to allow smaller friendly ships to travel great distances very quickly. Having a good enough network of Titans can allow an alliance to project it’s forces much further than they would otherwise be able to, allowing their line members to participate in important operations far away without leaving their home system, but it still requires scouts to light cynos for the ships to jump to.
Scouts are some of the most underappreciated members of an alliance. They do a lot of work in the shadows that allow the rest of the alliance to take war objectives and participate in the huge fleet fights that get on gaming news sites like PC Gamer or Kotaku. Without them an alliance would be flying blind.