On the Who Wants to Be a Millionaire? franchise, a free shot is the first question after a guaranteed prize had been reached, meaning that there is no danger/penalty for incorrectly answering the question.
Providing an incorrect answer to a 'free shot' question has the same effect as a contestant walking away with the cash prize they already have. For example, on the original British version of the show with its 15-question format, the free shots were at Question 6 for £2,000 and Question 11 for £64,000, meaning that answering either of the two questions wrong will force the player to leave with the current cash prize, not losing any money in the process.
The first question on the show is not technically considered a 'free shot' as at that point no money has yet been won. However, the contestant will still go away with nothing if an incorrect answer is given to the first question.
With the advent of the high-risk format and adjustable safety nets, it is theoretically possible to have a free shot at the £1,000,000 question by setting a safety net on the £500,000 question. While no one has managed to achieve this feat in the original British version, it has been done overseas: Jullie Dutra from the Brazilian version set her safety net at R$500,000 and had a free shot at the R$1,000,000, to which she answered correctly.
On January 5, 2016, Trần Thị Vân Quyền from the Vietnamese version was the first (and only) contestant worldwide to take the money on a free shot question (question 11).