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Once upon a time we had Hungarian notation, because IDEs didn't provide intellisense and programmers were too dumb to realise that having a 30,000 line long block of code was unreadable*. Nowadays IDEs are friendly, programmers have started using small, neat classes, we have JavaDoc and things in genral are easier to read.
So, just name your variable for its usage. i.e. names. I'm no fan of pre/post-fixing variables as it often makes them harder to understand.
(*) i.e. Me, there's probably some deeply shameful code out there with my name on it.