There are two main types of fund charges: one-off charges and regular/annual charges. All charges have to be disclosed before you invest.
An entry charge of up to 5% may be taken from your money before it is invested. Since 1 January 2013, it may not include commission to advisers, but platforms and execution-only brokers may take a percentage.
An exit charge of up to 5% may be taken before the proceeds of your investment are paid out. Very few funds have an exit charge, and they are usually in place of an entry charge.