...The U Turn on Tax Credits - http://www.theguardian.com/uk-news/2015/nov/25/george-osborne-u-turn-scrap-tax-credit-cuts-autumn-statement

Tax credits are state benefits that provide extra money to people responsible for children, disabled workers and other workers on lower incomes.
There are two types of tax credits – child tax credits and working tax credits. You can find out more about each type of tax credit on the relevant page. You might be eligible for one or both of them, depending on your circumstances.
Tax credits are tax-free and you don't have to be paying National Insurance or tax to qualify, but they are means-tested. So, whether you qualify and how much you get depends on your household's income and circumstances.