Doctor Who is a British science-fiction drama series produced by the BBC from November 23, 1963 to December 6, 1989, and again since March 26, 2005, with a television movie in 1996. It depicts the adventures of a time-travelling humanoid alien known simply as the Doctor, who as of 2013 has been portrayed by twelve different actors.
The original Doctor Who title sequence, designed by Bernard Lodge, used a distorting visual effect known as "howlaround", caused by pointing a TV camera at its own monitor. This effect had been accidentally created by Norman Taylor, at the time a technical operations manager at the BBC.
In March 1967, four months after Patrick Troughton succeeded William Hartnell as the Doctor, the decision was taken to refresh the titles. These retained the "howlaround" effect but also featured the Doctor's face, a practice that would be retained until the show's initial demise in 1989. The series logo was also refreshed, being rendered in Times New Roman font.
January 1970 saw the introduction of colour to the show as well as the 3rd Doctor: Jon Pertwee. Accordingly, Bernard Lodge refreshed the titles again, retaining the "howlaround" effect once more and introducing a specifically-designed series logo.
A completely new title sequence, once again designed by Bernard Lodge, was introduced in December 1973. This made use of a technique known as "slit-scan", first used in the film 2001: A Space Odyssey. Here, multiple exposures of light refracting in polythene plastic were filmed through different-shaped slits in black card on a rostrum camera, thus creating time-tunnel effects.
To go with this sequence was another specifically-designed series logo, in the shape of a diamond.
When Tom Baker took over as the Doctor in December 1974, the sequence was revised, with the "slit-scan" technique being further applied to an image of the Doctor's time machine, the TARDIS.
In 1980, the diamond logo was replaced by a neon sign-looking logo. The title sequence now has a space theme rather than a time tunnel theme, this time by Sid Sutton. Peter Howell also did a rendition of the Doctor Who theme.
When Colin Baker was introduced as the sixth incarnation of the Doctor, the crew felt like a new logo and title sequence was needed. It was more colourful, trying to fit into Colin's colourful outfit as the 6th Doctor. The logo is now purple and had a curve. Later at the time of this intro, a new rendition of the Doctor Who theme was made by Dominic Glynn.
When Sylvester McCoy was introduced as the seventh incarnation of the Doctor, it was also time to make a new logo, a new title sequence, and a new rendition of the show's theme song. The logo is a gold script reading out 'Doctor' and a purple text glowing red reading out 'WHO'. Not everyone liked the logo and the theme rendition. The title sequence was the first to be made in CGI for Doctor Who. It was also the first time we saw the TARDIS in the title sequence since the Tom Baker title sequence.
1996 TV movie
When the 1996 TV movie was released, it had a new(ish) logo. It was just a remastering of the logo during the time of Jon Pertwee, the 3rd Doctor, which is coincidental because Pertwee died in 1996, the year the TV movie aired. The only changes were the changes to the 'C', the 'T', the 'R' and the 'W'.
A brighter effect was added. The same famous shape was still the logo theme as it looked modern and fitted Doctor Who.
A brand new look. A brand new doctor. This was a huge change for doctor who as the opening sequance was very powerful and dramatic as thunder bolts etc were added for a modern effect.
For each episode of the 2012 series, the logo is retextured with a theme based on that particular episode. The font is very similar to the previous logo, however the 'DW' Tardis like logo in the middle of the title has been removed.
For the 2012 Christmas special, The Snowmen, the title sequence was totally redesigned, the snow themed logo was put in place but, for series 7 part 2 the logo had a white similar theme but without the snow effect.