quotation marks: to set off and represent exact language (either spoken or written)
plus sign: a plus sign is a binary operator that indicates addition or it can also serve as a unary operator that leaves it's operand unchanged (+x means the same as x)
pipe symbol: it separates 2 programs on a command line
or: is used to say you can add 20 or subtract 20
not: is used to say something is not available
I'm not 100% sure this is correct but I hope it helps
