When you create or edit a filter or an inventory rules folder, you handle the expression tokens as clauses or subclauses.
A clause is the combination of an expression token (or subclause) and its adjacent logical operator. You must add and delete expression tokens as clauses.
A subclause is a set of expression tokens that can be logically treated as a single expression token. A subclause starts and ends with an expression token. You can explicitly group subclauses with parentheses.
In addition to combining expression tokens with logical operators, you can group a set of expression tokens together. A group is a set of expression tokens that are explicitly grouped together with parentheses. You can group only a set of expression tokens that form a subclause.
By making a set of expression tokens a group, you ensure that the group's expression tokens are treated as a single entity. Groups have a higher operator precedence than the logical operators (AND and OR).
Groups make complex queries easier to read. You can also use groups to clarify how OR clauses will be evaluated.