Acts as taggable worth using?

[poipu]

hi, what is the purpose of using tags? does it just describe what a
title/item is about? is it worth using in a search engine? what is the
main benefit and how to use it? if i have a recipe form, do i just have
a tags text box where the user can add their own custom tags?

thanks.

[poipu]

This should help answer your question:

The fundamental point is that you let your users do the organization
and categorization of the content. Usually it’s them tagging content
they themselves have created, but it’s not unheard of to allow users to
tag content created by others (such as visitors tagging content /you/
create).