After signing their first record deal, their new producer, George Martin, insisted Pete Best's skills simply weren't up to snuff and ordered he be replaced. Lennon admitted they were "cowards" and made their manager, Brian Epstein, deliver the sad news to Best.

Though now he's become one of the world's most renowned drummers, the loyal fans who packed into the famous Cavern Club in Liverpool were none too pleased when Ringo showed up behind the band's drum kit in 1962. Best's handsome face had garnered him a loyal following, but obviously fans eventually warmed up to Ringo.

The masses of young girls who turned up for concerts, movie premieres, or to wave hello as the Beatles walked off the plane in a new city were apparently too distracted by their love for the lads to care about whether or not their bladders were full.

Lennon and McCartney quickly became one of the most celebrated writing duos in history with their seemingly endless string of chart-topping hits when they finally broke through to America, but they didn't just have fun with the lead singer's words.

For instance, if you listen closely to the background vocals on "Paperback Writer," you'll hear Lennon and Harrison crooning the lyrics to the classic French nursery rhyme, "Frère Jacques."

When the band was getting their start, playing all hours of the night at clubs in Hamburg, Germany, they also kept very close quarters in a small room with bunk beds.

Harrison admitted in The Beatles Anthology that this made things especially awkward when he crawled under the sheets with a woman for the first time — Lennon, McCartney, and their then-drummer Pete Best all actually applauded for him after the deed was done. Harrison joked, "At least they kept quiet while I was doing it."

Though their performance on the February 9, 1964, episode of Sullivan's variety show definitely sealed the deal for Beatlemania's eruption in the States, their actual American TV debut occurred on the Huntley-Brinkley Report a few months prior on November, 18, 1963.

Following the success of "Please Please Me" as a single, the record company wanted a full album as soon as possible. So, George Martin capitalized on the wild, live energy the boys perfected in Hamburg and recorded the entire Please Please Me LP in less than 13 hours — saving "Twist and Shout" for last so the taxing vocals wouldn't ruin Lennon's voice before the other songs were done.

In contrast, the whimsical tune "Yellow Submarine" took nearly a month to complete even though it was just one song, as their sound grew more experimental in the mid-1960s.

And inspired the Abbey Road song "She Came In Through the Bathroom Window" by quite literally using a ladder to crawl into the bassist's bathroom window while he was away from his home, helping herself to a few of his clothes and personal items as mementos.

The lyrics, "When I find myself in times of trouble, Mother Mary comes to me, speaking words of wisdom, let it be," led many to assume McCartney was referring to the spiritual strength found in the Virgin Mary.

However, he was actually being a bit more personal and referring to his own mother, Mary McCartney, who died of breast cancer when he was still a teen.

Ol' Blue Eyes would often perform "Something" from Abbey Road at his live shows, introducing it as the "best love song ever written." Unfortunately, he also credited that writing to Lennon and McCartney, an easy mistake considering they did write most of the tunes. Sinatra eventually corrected himself by 1978, properly citing Harrison for penning the romantic song.

Ironically, the loving lyrics weren't actually inspired by any amorous intentions on Harrison's part, instead simply hoping to create a soulful ballad that Ray Charles might like to record.

But she certainly didn't help. Tension was already building between the four musicians long before Lennon fell head over heels for the artist and refused to leave her side even for recording sessions, most famously captured while working on Let It Be.

One of the most heated moments during the sessions came between Lennon and Harrison after Harrison noticed Ono had taken his chocolate biscuit without asking.

As you can see, it just didn't take much to set the boys off by that point in their working relationship.

Though Let It Be was the final album to be released, about a month after they officially broke up in 1970, Abbey Road was actually recorded after it, marking their last time together in the studio.

There's obviously a lot of wiggle room here and fans still debate which one truly counts as the band's final offering, but you can't deny that the happier sound of Abbey Road is a much more cathartic goodbye for the four lads rather than the stress-filled fighting that went on behind Let It Be.

In the early days of their success, a reporter asked the bandmates what they would most like to do if it all went belly-up before they knew it. Starr calmly replied that he'd "always fancied having a ladies hairdressing salon."

While that dream never came true, he did eventually marry a hairdresser when he wed his first wife, Maureen, who was also from Liverpool.

Lennon's first wife and mother of his oldest son, Julian, detailed in her autobiography how, upon receiving a call from Ono with news of John's sudden death in 1980, it was also made clear that she was not welcome at the funeral.

Julian, who was 17 years old at the time, was sent on a plane from the U.K. to New York City all on his own, where his younger brother Sean still hadn't been informed of the horrible situation, as they weren't sure how the 5-year-old would handle the news.

In 2010, the Vatican released their official list of the top 10 pop albums of all time, and placed the Beatles' 1966 album Revolver at the number one spot!

Other artists who made the ranks include Pink Floyd, Fleetwood Mac, and Bob Dylan.

Believe me, I thought I had combed through every bootleg and rare tune ever leaked or released over the years, but I have to admit there were a ton of unreleased songs out there on the web that I had somehow missed.

Not only does this make us wonder how many other songs might be hiding in corners of the world, but it makes us even more impressed that a band who broke up over 40 years ago is still able to surprise us!