An Equity ISA (sometimes referred to as a Stocks and Shares ISA) provides a tax-efficient way to invest in a wide range of assets, normally stock market related, with the potential for higher returns than cash.
Equity ISAs are more of a long-term commitment than a Cash ISA, so they may be a better idea if you are saving for an event a number of years away, such as retirement, university fees for your child/grandchild or something more indulgent. Please keep in mind that with the prospect of higher returns comes some fluctuation in the value of your investments. At times they may even be lower than when you invested. However, over the long-term equity based investments are proven to out-perform all other asset types.