Meaning of characters in %, !, $ and # in variable declaration

Hello all,

This is my first time on this forum since normally I figure out a lot myself, but this time I can't. Does anybody know the meaning of the use of the characters %, !, $ and # in in variable declaration. I have inherited an Excel sheet with lots of VBA code in which many variables are declared with these characters, but I have no idea what this does. E.g.:

Dim j%, k%, kRow%, kCol%, colOff%
Dim fireRate%, hazDis!, pEscX!, pEsc!, pInc!, zFireType$, sRating$
Dim d2s#, tCx!, tCy!, thetaC!, xl!, yl!

He also uses '#' in a formula:
ir = f/t/2#, for which I also don't know what the # does.

Does any of you know what these characters do?

Many thanks for your help.

Integer(%),Long(&),Double(#)

:D Thanks guys!