What's the difference and which one should you use?
This was a question that I was asked on Quora (here).
Direct link is here: https://www.quora.com/What-is-the-function-of-control-key-and-B-in-MS-Word/answer/Russ-Crowley
I recorded a quick video showing some of the differences:
The ability to check consistent formatting is one of the main reasons why we'd use something like this.