A thread on Hacker News about the eternal confusion between / and :
jordanlund: Confession time… I always get confused about which one is the slash and which one is the backslash. I end up calling them “the one on the question mark” and “the one not on the question mark”.
zem: Here’s a simple trick: \ leans back, / leans forward.
grantrules: _ is a slash that got tired and lay down.
jmkogut: | is a slash that stands up straight.
gaoshan: ! is a slash that wears a hat and a sock. i is the same slash doing a handstand. ? is the same slash but very old and wrinkled.
knome: T is a horizontal slash that needs a vertical one to support it.
“Leans back” and “leans forward” is the mnemonic I use. Simple and it sticks.