Save this as file with extension .pl, you don't need anything more. On Windows you need also install ActivePerl (or Strawberry, but it may be harder for beginner). To run program you just need to type "perl" on command prompt, it is compiled in memory.

If you want to use Eclipse, you need to install EPIC Eclipse extension.

P.S. Consider reading "Learning Perl" (no earlier than 4th edition) or "Beginning Perl" - they both have good exercises.