Yield is a bit like an interest rate – it’s a measure of the income you’re getting. Having it as a percentage lets you compare the income from different investments.
When you invest, one element of your return is the income you can receive.
To compare income on different investments, investors calculate their yield.
The yield is usually expressed as an annual percentage rate, based on your outlay, for example, a £5 dividend from a £100 investment would be a yield of 5%.