Yep, the show is called “8 Out of 10 Cats Does Countdown”!
The ones you see on Youtube are the special episodes where the comedy troupe plays Countdown.
Listen, this is like seeing a quiz game and saying it's like Celebrity Jeopardy[1].
[1]: https://en.wikipedia.org/wiki/Celebrity_Jeopardy!_(Saturday_...
... "8 out of 10 cats" is a comedy troupe. Countdown is the name of the game, and in particular the Numbers Round: https://en.wikipedia.org/wiki/Countdown_(game_show)#Numbers_...