Free software available on the Internet for downloading. It is used and redistributed at no cost to the user. Shareware, on the other hand, requires that you pay a registration fee after a certain amount of time.
There are a lot of great freeware products on the Internet. Many are as good as, or even better than, their commercial alternatives. As of May 18, 2005 here are "The 46 Best-ever Freeware Utilities" as rated by Tech Support Alert - check it out!