Recording groups
From MythTV Official Wiki
Recording Groups
Recording Groups allow programs to be separated into user-defined categories, such as "Kids", "Alice", "Bob", etc. This can be used to reduce clutter, or to segregate content if PIN protection function is used.
In the 'Watch Recordings' Screen
press the 'M' (menu) key to change the view or to set a group password
press the 'I' (info) key to move a program from one Recording Group to another