MacKeeper is a program which often appears as part of “scareware” ads. These ads are designed to trick individuals into downloading potentially malicious software. Scareware ads typically generate pop-up windows that resemble computer system-generated messages indicating the computer is infected with counterfeit antivirus and antispyware software or a first aid utility software. We would highly recommend you remove MacKeeper from your machine.
One of the best anti-malware software tools available that Dana Hall recommends is Malware Bytes. Download a free Mac OSX version from here.
Courtesy of Malwarebytes