List of The Big Bang Theory episodes

The following is a list of episodes of the CBS sitcom The Big Bang Theory.

Like the name of the series itself, with the exception of the first episode - "Pilot" - episode titles of The Big Bang Theory always start with "The", and resemble the name of a, or , whimsically referencing a plot point, script line or quirk in the episode. The writers have used 104 different scientific principles in the episode titles as of 10 April 2014 with "hypothesis" used the most (five times) followed by "excitation", "reaction", "turbulence" and "vortex", four times each.

As of May 15, 2014, 159 episodes have aired.

Season 1: 2007-2008
The series The Big Bang Theory began its first season on September 24, 2007 in the United States and was picked up for a full run of 17 episodes.

Season 2: 2008-2009
The Big Bang Theory returned to television with Season 2 on September 22, 2008, and contained 23 episodes.

Season 3: 2009-2010
The Big Bang Theory returned to television with Season 3 on September 21, 2009, and contained 23 episodes.

Season 4: 2010-2011
The Big Bang Theory returned to television with Season 4 on September 23, 2010, and contained 24 episodes.

Season 5: 2011-2012
The Big Bang Theory returned to television with Season 5 on September 22, 2011, and contained 24 episodes.

Season 6: 2012-2013
The Big Bang Theory returned to television with Season 6 on September 27, 2012, and contained 24 episodes.

Season 7: 2013-2014
The Big Bang Theory returned to television with Season 7 on September 26, 2013 and the season contains 24 episodes.

Season 8: 2014-2015
The 8th season of The Big Bang Theory was confirmed on March 12, 2014 for a 3-year deal through May 2017.