Theft is defined under Section 1 of the Theft Act 1968 as dishonestly appropriating property belonging to another with the intent to permanently deprive them of it. There are five elements of theft: dishonesty, appropriation by asserting ownership over property, the property belonging to another, and the intent to permanently deprive the other person of the property. Property is broadly defined but does not include intangible things like information. The key aspects are that the property belongs to someone else, not the defendant, and that the defendant intended to permanently deprive the owner of the property.