Fifty years ago today, many American teens were filled with anticipation. A new band was coming to the U.S. Their arrival would become a milestone in our cultural history.

Many say it was a simpler time. Television was relatively new. Families gathered together to watch favorite shows such as "Leave it to Beaver" or "The Andy Griffith Show." There were fewer distractions, no Internet, no smartphones or video games. If you were a youngster then, you might have heard of the Beatles. You might not have, yet. But Sunday nights were probably spent sitting in front of the television watching "The Ed Sullivan Show." For many, that meant stumbling upon a moment that would go down in history.

Elvis Presley, The King of Rock and Roll had already shocked America, swinging his pelvis wildly on the Sullivan show as parents shuddered in scandal. Singers Pearl Bailey and Leslie Uggams' appearances were pioneering moments for black entertainers. And then came the Beatles' British invasion. They arrived to screaming crowds, shaking their moptop hairdos and wearing Edwardian collarless suits and tight-fitting boots. They looked different, they sounded different and popular music was transformed. They were something new: the sound, the lyrics, the celebrity. Other groups such as The Kinks and The Who imitated them but never quite captured what they had. They went on to make musical history.

A lot can happen in a single generation. Now that 50 years have passed since the invasion, the Beatles' legacy can begin to be understood. As Bob Dylan's 1964 song explained, the times, they were a-changin.' It was an epic time which was followed by civil rights, flower power, riots and Vietnam. The nation lost much of its naivet?and innocence while becoming more tolerant and inclusive. The debate will never end as to whether that change was good. But we know the country would never be the same.

American music's eventual descent into rap and heavy metal may make some long for Elvis' gyrations, which now seem tame compared to Miley's twerking.

No matter what you think of today's music, much of the nation's cultural change began with the Fab Four.

So in commemoration of their explosion into popular culture, hold your loved one's hand and listen to "She Loves You" or "Norwegian Wood" and reminisce.