It can be used as a word substitute for "or" when indicating a choice.
I sometimes see it being used in an effort to make a strong connection between words.
- The Hemingway/Faulkner generation
I've also seen it used when there is conflict between two things.
- The nature/nurture debate
I quickly discovered this in university when I had to take notes quickly - abbreviations.
- w/o = without
- w/ = with
- b/w = between
- n/a = not applicable
- 7.5 hours/day
My personal favourite - because the irony is, not many people can read it - is when it's used in phonetics. You know what they are. You see them in dictionaries right after words to show you how the words are pronounced.
- My name is Bonnie. This is how you write it out phonetically /bɒni:/
- Slash looks like this /slæʃ/
I know I haven't addressed everything. Some other uses of the slash can be seen in poetry (line breaks), fractions (math), dates, web addresses, and emojis. I think everyone knows those.