Language/English/Vocabulary/Difference-between-ROBBER,-BURGLAR,-MUGGER-and-THIEF
Burglar
Someone who breaks in / forces his/her way into a building so as to steal something. It could be a home, office, factory and so on.
Robber
Someone who threatens violence so that he/she can steal something from someone. If the threatened person does not permit the robber to take what the robber wants, then the robber will be violent so that he/she gets what he/she wants.
Mugger
Someone who uses violence without any warning to make it possible / easier to steal something from someone. It could be a criminal hitting someone on the head then stealing something from that person.
Another one not on the list but common is ”pickpocket”.
Pickpocket
Someone who steals from someone’s pocket, coat or bag without that person realising that he/she is having something stolen. The thing stolen is directly on the victim, not somewhere else such as on a table.
Thief
Someone who steals something without threatening violence. Burglars (usually) and pickpockets can also be classified as thieves (the plural of ”thief”). Someone who takes someone’s wallet from a desk by just walking through a door is a thief, but not a pickpocket or a burglar.