What is a trust?
A trust is where property is transferred in such a way that one person has control of the property while another person gets the benefit of that property.
There are two different aspects to owning property - the so-called legal title and the equitable title. Generally, when you own property, you have both of these titles in the property, which means that you own the property outright and can do whatever you want with it. However, there is no requirement that both of these titles be held by the same person.
For example, I may own the legal title to a house while you own the equitable title. By owning the equitable title, you are entitled to the use and benefit of the house, and by owning the legal title, I have a duty to care for, maintain and control the house. Similarly, I may own the legal title to a bank account, while you own the equitable title. While you are entitled to use the money in that account, I am responsible for giving you access to that money.
A trust, creating such a split between the titles in property, is useful where you want to give property to someone but you want to have some restrictions or limitations on it, as opposed to giving them unfettered use and access. For example, rich parents often set up trust funds for their children, requiring their children to comply with certain conditions to get access to portions of the money, rather than simply dumping a large amount of money on their children.
The person who creates the trust is known as the settlor or donor, the person who gets the legal title (control of the property) is known as the trustee, and the person who gets the equitable title (the use and enjoyment of the property) is known as the beneficiary.