Credit unions are usually small, not-for-profit organisations, owned by their members. They don’t have ‘shareholders’ like the big banks, so are generally run for the benefit of the community. Traditionally they mainly offer savings accounts and loans, but more and more now offer more products like current accounts or even mortgages. Once you save with them, you will generally become eligible to borrow from them too. The benefit of this is that the interest rates they are allowed to charge are capped by law so credit will be offered at very reasonable rates.
They are often less strict about only offering services to people with good credit, so people who tend to be excluded from banking can often get accounts with them.
In Manchester there are two main Credit Unions
There are also a number of credit unions people can join if they are in certain jobs, such as the Police.
You can search to see your local credit union or any job-related credit unions you can join here: http://www.findyourcreditunion.co.uk/home