SuperDuper is a popular, powerful, and easy-to-use app for quickly creating a fully bootable backup (or "clone") of your hard drive, whether you're recovering from a mishap or just migrating between machines. Even better, SuperDuper is free if you don't want to pay for its more advanced features, including scheduling, scripting, and "Smart Updates" (which save you time by making incremental updates to backups using only recent changes).
SuperDuper's interface sets out to make backups painless. Less technical users will love its friendly, plain-language approach--for example, explicitly explaining what will happen when you press a button. More-experienced users such as admins and QA testers will find plenty of more sophisticated features, from premade and customizable scripts to the ability to easily maintain multiple OS versions across different drives. SuperDuper comes with a full user guide, responsive support, and access to active forums.
Data loss is inevitable, and every Mac user should have a reliable backup system. SuperDuper makes the process easy, effortless, and almost enjoyable.