From: Eduardo Scoz
> What's the diference between regular variables defined as, lets say
> "example", and the ones defined as ":example" ? If there's a
difference,
> when should each case be used?

Items that start with a colon are not variables, they are Symbols.
Continue your research with that bit of information; there's a lot out
there on the difference between Symbols and Strings (in 1.8), and when
to use them.