My keyboard can only produce 95 characters? I have heard from multiple sources that a standard QWERTY keyboard can produce 96 different characters, not counting the option key characters. Here is a picture of my keyboard:



I highlighted in red the alphabet keys, which can produce 52 characters–26 lowercase and 26 uppercase letters. In blue is the symbolic keys, which can produce 22 characters–11 buttons, two for each. In green are the numbers, which can produce 20 characters–10 numbers with 10 symbols. Orange keys can't produce any letters. And there's also the space bar, delete, and return. Only the space bar can produce a character, a space.

In total, that is 52+22+20+1=95 characters? What is the missing character? The best guess to me is enter/return, although that doesn't really make a character to me.

I have a Macbook Air.
There are two different kinds of "standard" keyboards, ANSI (like in your picture) and ISO.  The former is sold in the US, the latter in Europe.  

References you have seen to 96 characters are presumably for the ISO version. It has one key more than ANSI version, which is located to the left of the z. Your keyboard is ANSI and has 95. 

To see the different kinds of keyboards made by Apple, go to

https://support.apple.com/en-us/HT201794