Hi @KrishnenduB
Those a simply indicators of the type of token that is being referenced.
% = Variable token, as in [%NoofShares]
! = Data base token, as in [!customerName]
? = formula
* = 'system' token, such as [*DATE] or [*DESKTOP_DIRECTORY]
@ = emulator key token, which won't be an option unless you're working with an emulator
^ = keyboard token, such as [^Ctrl+S] or [^Enter]
(I believe that is all of them, I'm sure Mathias will chime in if I forgot one :smileyvery-happy: )
Like you said, these are automatically added when you select a token in the Expression Builder so you don't have to worry too much about memorizing what each does. This may happen naturally over time, and at that point typing might be faster going thru the Expression Builder, but Nintex RPA will never require you to memorize these tokens.
Thanks,
John