The Big Bang Theory's first two seasons were released on high-definition Blu-ray today for the first time in the United States and Canada. The new box-sets include the episodes in full HD, along with standard definition DVDs and UltraViolet digital downloads (U.S. only), giving you a variety of ways to enjoy the early seasons of The Big Bang Theory.

The Big Bang Theory was first released on Blu-ray with its third season and since then  every passing season has been released on both DVD and Blu-ray, leaving fans wondering when the first seasons would get the high definition treatment.

The Big Bang Theory: Season 1 Blu-ray includes all seventeen episodes of the show's premiere season. This box-set includes the "Quantum Mechanics of The Big Bang Theory" featurette, which was included on the original DVD release. This box-set also includes a new, previously unseen gag reel from the season.

The Big Bang Theory: Season 2 Blu-ray all twenty-three episodes from the show's 2008/9 season. This box-set does not include any new bonus features, but it does contain the original DVD bonus features: "Physicist to the Stars" featurette, "Testing the Infinite Hilarity Hypothesis in Relation to The Big BangTheory" featurette, and a previously-released Gag Reel.

By the way, the upcoming The Big Bang Theory: Season 5 Blu-ray release will also be a combo box-set including Blu-ray, DVD and UltraViolet downloads. Fans in the United Kingdom might be interested to know the entire first five seasons of The Big Bang Theory will be released on Blu-ray there on September 24th in an Amazon.co.uk exclusive.