ISA, standing for individual savings account is essentially a tax wrapper, so think of it like a jacket for your account. If your money is sat in an account, with whatever the underlying investments may be, an ISA can surround this money like a tax efficient jacket. With this jacket, anything within the account grows tax free - meaning any investment gains and growth are completely free of tax, any gains in stocks and shares are free of capital gains tax and any withdrawals are tax free.

Simply put, an ISA is a tax free savings account.