This is just a simple way to compare how large of a Dividend one company is paying compared to another. An example of a Dividend Yield is if the Bitesized Money Inc share price was £100 and they paid a yearly £3 dividend, then the Dividend Yield would be 3% (£3 is 3% of £100). The higher this percentage, the higher the Dividend return you will get on your investment (a 4% Yield would pay £4 per £100 for example).
You don’t have to do this maths yourself though as any decent trading platform will do this for you. As an example, looking a Barclays Bank stock on Google Finance (Barclays), you can see at the time of writing it states “Dividend Yield – 3.77%”. So in simple terms, for every £100 of Barclays stock you own, they will give you £3.77 in cash this year.