1. This video is 21 years old.
2. Harry Styles wasn’t born when Boyzone made their first TV appearance.
5. Justin Timberlake has been out of NSYNC for longer than he was in it.
6. When O-Town sang about ‘Madonna’s wild style’ in “Liquid Dreams”, this is what they were referring to.
7. This photo of Billie Piper and Ritchie from 5ive dating is 15 years old.
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8. The Backstreet Boys celebrate their 20th anniversary this year.
14. “All Rise” by Blue is the same age as the iPod.
15. When Westlife released “Flying Without Wings”, the Daily Mail website looked like this.
16. Justin Bieber was born the year that “Stay” was Christmas number one.
Also 21 years old.