A Trust controls the distribution of assets that are in the Trust.
A Trust that is revocable is known as a "living trust". It can be amended and revoked.
The person who sets up the Trust is known as the "Trustor". The person who administers the Trust is known as the "Trustee". In a joint Trust (husband and wife) there are two Trustors and two Trustees.
The primary purposes of a Trust are:  to avoid probate;  to distribute asset upon death of the Trustor(s); and  to provide for the support and education of children. It can also be used to minimize estate tax.
A Trust only controls property that is in the Trust. Real property is deeded to the Trust. Tangible personal property can be assigned to the Trust. A Trust can be designated as beneficiary of financial accounts such as brokerage, 401k and IRA accounts. A Trust can also be designated as beneficiary of insurance policies.
In a Trust a "Successor Trustee" will be named who will administer the Trust if the Trustee or both Trustees are not living.