Tab Is 4 Spaces

What?

1. Indentation should be 4 spaces

   It's the best compromise of spacing for clarity and readability on most modern screens

   Even your editor doesn't have tabs, or say you're stuck using a simple notepad application then it's also pretty easy to maintain 4 spaces manually.

2. Must never be an odd number of spaces

   3 or 5 spaces are never acceptable. Generally, humans like things in 3s or 5s, our whole lives are based on groups of 10. But even numbers are superior.

   Not worth talking about 1 space, that's a mistake that you're too lazy to fix.

3. 8 Spaces?

   4 space so nice, let's do it twice.

   Previously with the 80 character wrap limit, it would have been a waste, but nowadays most screens should much more than 80 characters and so this works. It's an even number, it's two times 4 spaces.