An Article 4 direction can be made under the Town and Country Planning (General Permitted Development) (England) Order 2015 which withdraws permitted development rights that exist for certain types of uses.
Permitted development rights normally let homeowners make minor changes without needing full planning permission, or allow the change of use of a building without going through the planning permission process.
When an Article 4 direction is made, planning permission is needed for the type of development specified in the direction.