Tag settings
From MoodleDocs
Site administration settings
Enable tags functionality
By default, site-wide tags functionality is enabled. If this is not required, tags functionality may be disabled by an administrator by un-checking the usetags box in Settings > Site administration > Advanced features.
Show course tags
The Tags block has one setting which may be changed by an administrator in Settings > Site administration > Plugins > Blocks > Tags.
- Show course tags - This enables students to tag courses