Yes,you seen it right.Google has contributed itself in many open source projects.
Being an influential giant in tech world it has contributed in open source projects to pull other noob developers to do open source projects.Doing open source projects does not mean that the developers can’t get revenue for their projects,but it results or pays in other ways like getting jobs from tech giants directly for their contributions.
Now coming back,lets see the list of top open source projects released by google.
- Chromium os
- Angular js
- Material Design os
- Fuchsia os
- protocol buffers
- Google web tool kit
- VSAQ(vendor Security Assesment Questionnaire)
- Science Journal
these were the few projects,there were numerous not listed.Go and see the official site mentioned to know more
to see the complete listing visit google open source site