Welcome to Instant Slic3r. So you've decided to try out Slic3r for your 3D printing process. Maybe you chose it because it could print support material. Perhaps you chose it for its ability to lay out a whole plate of objects while still allowing you to print only one.
You may also like how you can use either a graphical user interface (GUI) or the command line to run Slic3r. You might even be using Slic3r already in one of several software packages, such as Pronterface, ReplicatorG, or Repetier-Host, and want to know more about Slic3r, or want to upgrade the version that came with your software package.