Brackets in an equation are handled as if they are parentheses. If you have parentheses inside of other parenthese, it is easier to read if a set of parentheses is replaced with a set of brackets.
Now, there are situations where brackets can have other meanings; for instance, if you are using matrices, brackets can represent matrices, but if you aren't using special functions, they just work like parentheses.
Brackets in an equation are handled as if they are parentheses. If you have parentheses inside of other parenthese, it is easier to read if a set of parentheses is replaced with a set of brackets.
Now, there are situations where brackets can have other meanings; for instance, if you are using matrices, brackets can represent matrices, but if you aren't using special functions, they just work like parentheses.