Chuck Lorre and Bill Prady's The Big Bang Theory is CBS' longest-running sitcom, with 12 seasons and a total of 279 episodes. Although it received mixed reviews during its first seasons, it went on to become one of the most popular sitcoms ever. The first seven seasons of were ranked within the top ten of the final season ratings, and it ultimately reached the number one spot for its eleventh season.

Although it came to an end in 2019, TBBT remains one of the most popular sitcoms of all time. One of the main reasons the show is so popular to this day has to be its iconic characters, brought to life by an incredibly talented cast.

Moreover, TBBT had plenty of memorable lines and jokes. It's hard to hear the word 'Bazinga' without thinking of Sheldon Cooper.

Plus, this popular sitcom had the most iconic theme song. 'The History of Everything' turned out to be the perfect fit for the show. It's hard to believe that the band who created this incredible theme song almost didn't write it!

The Original Pilot Of The Big Bang Theory Had A Very Different Theme Song

If you're a big fan of The Big Bang Theory, you probably know that the original pilot didn't include Penny.

Instead of Haley Cuoco's character, there was another female character named Katie, who Sheldon and Leonard meet outside their apartment building and invite to live with them. While they loved Sheldon and Leonard, the test audience absolutely hated this main female character. So, Chuck Lorre and Bill Prady, the show's co-creators, had to rewrite the pilot.

They got rid of Katie and wrote in Penny instead. Originally, Prison Break's Jodi Lyn O'Keefe had been originally cast to play this aspiring actress. But the actress was let go from the show after the initial table read. A ton of great actresses were then brought in to audition for the role.

Even MCU star Marisa Tomei read lines with Jim Parsons for the role of Penny. But, ultimately, the show's co-creators chose Kayle Cuoco.

But the main female character wasn't the only thing that changed in The Big Bang Theory after the pilot was rewritten. The original theme song was also discarded. Initially, the show's creators had used Thomas Dolby's hit "She Blinded Me with Science" as its theme song. But, ultimately, decided to go for an original song instead.

Who Is The Band Behind The Big Bang Theory's Iconic Theme Song?

The Big Bang Theory is an iconic sitcom with a memorable theme song. Titled 'The History of Everything,' this iconic song summarizes everything that's happened on this planet since the Big Bang. This catchy song was written by the Canadian band Barenaked Ladies. Even if the name doesn't ring a bell, you'd be surprised. This band has written songs for many popular films and TV shows.

Barenaked Ladies was formed in 1988 in the suburb of Scarborough, Ontario. In 1991, the band developed a cult following all across Canada shortly after their self-titled cassette was released. Although they tried to make it in the U.

S., they didn't get their big break until 1998, when they released their fourth studio album, Stunt.

Their fourth album included the single 'One Week,' which was used for the soundtrack of movies like American Pie (1999) and 10 Things I Hate About You (1999). Most recently, 'One Week' inspired an iconic line of dialogue in What We Do in the Shadows. Since the late 90s, plenty of Barenaked Ladies have been used in the soundtrack of 77 movies and TV shows!

The Barenaked Ladies Almost Didn't Create The Theme Song For The Big Bang Theory

In 2007, Ed Roberston from the Barenaked Ladies was approached by Chuck Lorre and Bill Prady to create a theme song for their new television series, The Big Bang Theory, after they saw the band in concert.

The singer was reluctant at first because he hadn't had much luck writing music for film and television before, but he accepted when he learned that they were the first and only choice for this project.

Robertson was lacking inspiration, so he hadn't written anything by the time he was supposed to meet with Lorre and Prady to show them the song. So, he almost backed down from the project.

"I totally ignored the entire thing until the morning I was supposed to get on a conference call with Chuck and Bill and present the song…which I had not written," Robertson told Metro.co.uk. "I was going to get on the call and just go 'hey guys, really appreciate the ask, but I've just been too busy with touring and I haven't been able to do this, so good luck.

'"

Ultimately, he decided to try his luck and write a song for the show after he was struck by inspiration while taking a shower. "I got in the shower and the whole idea came to me in the course of a five-minute shower. I actually called my wife in and said 'Can you write this down?!?' and dictated the first verse to her," the singer revealed.

He then recorded the song and send it over to Lorre. The co-creator of TBBT loved it. After making some small tweaks and shortening the song to 15 seconds, the band went on to record this iconic theme song. And the rest is history!