In typing, proper style is 2 spaces after a period (.), as well as after a colon (:).
no spaces
2 Spaces
2
1
Commas do not go at the end of sentences. Periods go at the end of sentences. Generally when typing on a computer, you should have two spaces after the period at the end of a sentence.
no spaces
2 Spaces
It used to be 2 spaces but nowadays it is only 1.
one
2
2
one space after and abberviation two spaces at the end of a sentence
One space follows a period after an initial.
One.
1
How many spaces do you need after the word period? Is she having her period.
When I grew up, every period was followed by 2 spaces. However, I have heard they changed this to 1 space.