Google Docs is Google's document publishing app, in many ways like Microsoft Word. The interface is very simplistic with many icons and options that most users familiar with publishing software are accustomed to including font type, font size, Bold, Italics, Underline, font color, etc. There are many more advanced features of Google Docs in the tab headings and in the Add-Ons store.
There are many things that make Google Docs exceptional and a few of those are:
Google Help Center: Docs