coil overs or springs

whats the difference im about to go lower and i dont knwo whats better and easiest to work with coilovers or springs i put my springon last time is it just as easy with coilovers how do the work

coilovers allow you to generally have:
-adjustable dampening (shock rebound adjustment. soft to hard shocks)
-adjustable ride height (raise or lower your car as according)
-interchangeable springs (change springs with higher or lower, harder or softer, spring rates)
-adjustable ride height by lowering the dampener within the mounting bracket (allowing you to lower you car by lowering the entire shock setup, NOT just the spring. this allows you to lower your car more, but still utilize the ENTIRE shock/dampener distance, unlike lowering springs or cut springs (or people who improperly use coilovers) which drop your ride height but also lessen the dampener travel, thus utilizing less percentage of the intended shock travel)

what year make model are you looking to buy for? what do you intend to use the car for? and what is your price range?

you really wanna learn some shit spend a bit reading this lol, its educational:
http://www.pirate4x4.com/tech/billavista/coilovers/Part_1/