If you have a spare hard drive lying around, you could use the existing recovery partition to install the OS on to that, even if just temporarily. If you have a friend with a Mac, he could download ...

Formatting a hard drive along with the install of a new OS is the best option. The vast majority of operating system installations provide a "format" option as part of the installation process.

You may want to format your hard drive if it contains outdated business files or communications. A system recovery disk contains your as-shipped operating system. Used to format the hard disk, it ...

[Editor’s note: This article is part of our series of articles on installing and upgrading to Lion (OS X 10.7). We also have a complete guide to installing and upgrading to Mountain Lion (OS X 10.8).] ...