Find&replace, () and [] brackets

[altair]

Hello!
Please, what is the main difference in usage of round and square brackets in find&replace?

I think, () is for OR options (x | y)

[aeiou]= [a,e,i,o,u]

If someone knows a good link where to find more informations, I would be so incouraged to ask for!
many thanks!

[mariosv]

Hi Altair, have you search in the inner?. In Index tab search for “Regular expressions”