They call it the "Magic Plastic"

Intro
People familiar with canons lenses, know this lens is a must. Most would say its an essential, and if you are just getting into photography, you would have to be nuts not to have this lens.

Construction
Its simple construction being a prime lens, meaning it has no adjustable zoom means there are no moving pieces aside from focus and only a few elements of glass inside. This causes the lens to produce extra sharp images. Most prime lenses produce sharper images, but most prime lenses cost hundreds of dollars. This lens can be found at pawn shops for $50 or less and sells for $80 new.

1.8 Fstop
This lens features a 1.8fstop which means it can focus on objects sharply and get alot of blur on the background making the object stand out (depth of field). It also means that this lens can shoot in low light, and still get a sharp image with good color.

Metal Vs Plastic Version
The newer version of this lens is made of plastic, thus the nickname "magic plastic" but the older version was made of metal. Many photographers prefer the metal version since it should last longer.

Summary
This lens is a must for any photographer, experienced or not. At the price it sells for brand new, and the pure ammount of them out there used. Its a great buy.