Fighters are cheap(individually) effective ways to make a base or fleet more powerful. Most ships carry weapons designed to kill other ships, not fighters.

You build fighters at a fighter plant using the base`s parts order screen . The new fighters will end up in base storage next turn. The fighters that are stored at the base will be used to defend the base from enemy ground attacks against the base. (Some ships can build fighters)

When the base comes under attack the fighters on the base will form home guard fighter wings that will attack the incoming ships.

If you have an air attack base on your base you can form a new fighter wing. A fighter wing can leave a planet under its own power and travel to other planets just like a ship. When a wing ends up parked over any base you own or next to any ship that you own it will automatically be refueled and rearmed. This happens atthe end of movement phase.

Fighter wings can dock with ships with fighter bays and travel inside the carrier ship. When a ship gets into a fight the fighters will automatically undock and attack the enemy (unless ordered not to). If the fighters`s mother ship is destroyed in combat the fighter wings will remain in deep space waiting for new navigation order or a carrier ship to dock with.