Offences Against Property
(1)-(3) All robbery is either theft or extortion. Theft is robbery if the offender, to commit/carry out the theft or retain/escape with the stolen property, voluntarily causes or attempts death/hurt/wrongful restraint (or fear of the instant version of these). Extortion is robbery if committed in the victim's presence by putting them in fear of INSTANT death/hurt/restraint, inducing immediate delivery. (4)-(6) Robbery is punished with up to 10 years' rigorous imprisonment plus fine (up to 14 years if committed on a highway between sunset and sunrise); attempted robbery with up to 7 years plus fine; and robbery/attempted robbery causing voluntary hurt with life imprisonment or up to 10 years' rigorous imprisonment plus fine (applying to every person jointly involved).
This defines robbery as essentially theft-plus-violence or extortion-plus-immediacy - the key distinguishing feature from simple extortion is that the fear induced must be of something happening INSTANTLY, right there, rather than a threat of future harm.
A mugger who threatens immediate violence face-to-face to force a victim to hand over their wallet on the spot commits robbery (not mere extortion), specifically because the threatened harm is immediate rather than a threat about the future.