If you are using this version for legacy projects or learning, it introduced several groundbreaking tools that are still staples in vector design: Adobe Illustrator CS5 - My Top 5 Favorite Features
to bring up a grid that lets you draw objects as if they are on a 3D wall. 3. Working with Vectors Unlike Photoshop, Illustrator uses (mathematical paths). Adobe.Illustrator.CS5.Lite.Portable