Technically it's google, but there are a ton of search engines. Literally 100's of thousands. I can't see any pushing google out of the 1st place spot anytime soon, but stranger things have happened. Anyone can create a search engine now a days.
If your interested in building your own search engine. Go here - http://bit.ly/1adRXWk
I'm personally using ecosia, after years spent using google. What i most like about it is the fact that they plant trees in brazil each time you use the site, so you're also helping out the environment while searching.
