Google Docs is part of Google Drive. So, you can access this word processing application directly from Google Drive.
As a word processing application, Google Docs can be used to type and edit text. Its function is not much different from Microsoft Word. But the files you create in Google Docs will be directly saved in Google Drive.
In most cases, each computer will have more than one browser installed. This is common because any browser can be an alternative to browsing activities. The existence of several browsers can be another alternative if the browser used is problematic for some reason. Using more than one browser can also provide a different browsing experience.
Of the several browsers on your computer, one browser will certainly be your favorite browser for browsing activities and another may only be used occasionally. Due to being a favorite browser and one that is often used, you may already have a lot of bookmarks in that browser.