Everyone in EVE Online understands the basic idea of Tracking. The basic idea that turrets must be able to spin fast enough to keep up with the target to maintain an accurate aim on that target.
Ex: A Battleship cannot track a frigate orbiting it at 500m.
But that's only half the story...
Two other stats called Signature Radius and Signature Resolution decide how much damage your turrets do to an opponent.
Signature Radius is the size of a ship. Picture this as a bubble the size of your ship.
Signature Resolution is how precise the aim of a gun is. For example, imagine a rifle shooting a target. The rifle is setup so that the aim is exactly the same every time it fires. Yet when you look at the target there is more than one hole. instead there is a "grouping" of holes. This "margin of error" is kinda like the Signature Resolution.