Alphabet Inc. is the parent company of Google, in addition to a series of subsidiary holdings. These cover engineering (Waymo for self driving cars, Intrinsic for robotics), health companies (Verily, Calico, Isomorphic labs), investment (Capital G and GV) and research (X Development).
In a recent case, Alphabet Inc. was ruled to hold an illegal monopoly in the search market via Google Chrome, and the DoJ has called for the selling off of Chrome. Possible buyers include OpenAI and Yahoo!.