Navigating on the internet sometimes I get this webpage "mackeeperapp2"
These are pop-up ads, usually opened in new tabs or windows, by aggressive sites that are paid by the makers of MacKeeper to advertise for them. The appearance of these advertisements has nothing to do with the state of your Mac -- your computer is good, safe and fine.

The MacKeeper application itself is not well regarded:


  MacKeeper has been described by various sources as highly invasive malware that can de-stablize your operating system, adding that it is unethically marketed, with a history of making false advertising claims, by a company called Zeobit, and a rip-off.