Burglar-resistant door is the general name given to any door designed to resist an attempt at forced entry. In homes there are mainly two types: the security door, with steel sheeting inside the leaf, and the armoured door, with an all steel structure.
What they have in common is that they work as a whole: a reinforced leaf, a lock with several locking points, a security cylinder, an escutcheon, strong hinges, hinge bolts and a firmly anchored frame. If one of those parts fails, the door is only as strong as its weakest part.
There is a European standard that classifies doors by grades of burglar resistance. If you are going to buy one, ask about that grade and do not settle for the word “security” on its own. On security doors, which are the ones we fit, you will find more in security doors.