what is the yahoo message filter about?

Question

and how is it used it.

Answer 1

Yahoo! Mail uses message filters to sort e-mail messages. They sort using if...then... filters. For example, if "From header: contains Bobby" then "Move the message to: Friends folder."

You can access the e-mail filters by going to Options > Filters > [Add]. Next, setup your filters.

The free version of Yahoo! Mail provides 15 filters.