What is this "A/a" button/tab/icon thing, and how do I get rid of it?

[AC Question]

I just switched from iPad to an Asus tablet. What is this "A/a" button/tab/icon thing on the side of the screen that looks like a book and can be moved around? It's there when I have any app open. How how do I get rid of it? I don't want it.

Thanks!

 

[Fedginator]

Can you send a picture?

Posted via the Android Central App

 

[Rukbat]

That's normally used as a keyboard shift indicator. A large A/small A icon is normally font size.