By Kristi Mckinney , eHow Contributing Writer People mean many things when they use the term "Reset." For oururposes, reset means restoring your MacBook to the operating system (OS) setup it contained when you purchased it. It does not mean resetting your MacBook's PRAM, resetting your MacBook's system management control (SMC), resetting passwords or resetting any other specific settings. You may want to reset your MacBook for a variety of reasons, from updating your OS to needing to install new hardware. Difficulty: Moderately Easy Instructions Step 1 Back up your information to an external medium such as an external hard drive or a flash drive. The install process allows you to transfer current files to a fresh operating system (OS) install, but it is always best to be prepared with a backup of your files in case something goes wrong. Step 2 Insert the first install CD or DVD of the operating system software . Step...