The blagger's guide to Doctor Who Who is Doctor Who? Well, for starters it's just "the Doctor." Fans get irate when he is referred to as 'Doctor Who'. No one knows what his real name is and it's one of the show's biggest secrets. Anyway, he's an ancient Time Lord with two hearts from the planet Gallifrey. Did you say "ancient"? He only looks about 30. He's an alien, so he can regenerate. It means that once the actor playing the Doctor wants to move on, they can hand over the reins to someone else by regenerating. Matt Smith is the eleventh person to play the Doctor and he will be passing the baton on to The Thick of It star Peter Capaldi this Christmas. The Doctor only has 13 lives - although this is up for debate... it's complicated. What's with the blue box? That's the Tardis. It stands for Time And Relative Dimensions in Space. It's the Doctor's time travelling machine that can take him anywhere in time and space. It's not actually a Police Box from the 1950s, it used to be able to change into any object and blend into the background, but one day its chameleon circuit got stuck, now it always looks like that. It's also bigger on the inside than the outside. That must impress the ladies... speaking of which, he seems to change girlfriends often. They're not his girlfriends. They're known as "companions," they travel through time and space with him. He's travelled with many companions over the years, including a robotic dog called K-9 and a Time Lady. He has had male assistants in the past, it just happens that a large proportion of companions are young, attractive women... Clara and the Doctor speed through London on a motorbike (BBC) So, he travels a lot. Been anywhere nice recently? Not quite, he always seems to be stumbling into perilous, life-threatening situations where he has to save the day. Over the past 50 years he's travelled all across time and space. He's met everyone from Vincent Van Gogh to Henry VIII to Marco Polo. The Doctor has saved the Earth countless times. He's also made many enemies along the way, including the Daleks. Are those the robots with the plungers and whisks that say "exterminate"? Yes, although, that's actually an eye stalk and a laser gun. The Daleks are the Doctor's arch nemeses and he has defeated them countless times over the years. Contrary to popular belief you can't escape them by running up some stairs. The Daleks can fly and are considered one of the scariest villains on the show. The Doctor's great foe: the Daleks (BBC) What's that wand thing he's always carrying around with him? That's the sonic screwdriver. Admittedly, it's not as impressive as the Tardis but size isn't always everything. The sonic screwdriver has helped the Doctor out of quite a few sticky situations. It only used to function as a torch and unlock doors but now it does so much more, from scanning substances to cutting through walls. It just wouldn't be Doctor Who without the sonic screwdriver. What's all this fuss about the 23rd November? This year marks the 50th anniversary of Doctor Who. It's the longest-running science fiction television programme in the world, even beating Star Trek. The show initially ran from 1963 to 1989 before getting cancelled when it fell out of favour with BBC bosses. However, following years of campaigning and even a film, Doctor Who returned in 2005 and has been on the air ever since. To mark this landmark year there will be a shed-load of Doctor Who-related programming and events on Saturday 23 November, the day the television series first aired back in 1963. The "Doctor Who" 50th anniversary special "The Day of the Doctor" will be on 23 November on BBC1