OptimalUnit is an adware affecting Mac users. It will attempt to commandeer one’s browser search and homepage promoting a fake search engine. This adware will generate lots of unwanted advertisements on your browser in the form of fake surveys, coupons, pop-up ads, and banners. These intrusive ads will send you to malicious websites to get money from you or infect your computer further. It may also prevent you from changing your settings back.
OptimalUnit is usually installed through bundled software without you knowing. Remove it immediately before it will further damage your Mac.