Katy Perry's breakthrough album, One of the Boys turns 10 today.

The album spawned the megahits I Kissed a Girl (#1 on Billboard Hot 100) and Hot N Cold (#3 on Billboard Hot 100). Other singles are Thinking of You and Waking Up in Vegas. Katy's breakthrough single Ur So Gay is also on this album. The album peaked at #9 on the Billboard Top 200 albums chart.

OOTB was nominated for 2 Grammys and sold over 7 million copies worldwide. The music videos released for the singles are some of the most innovative of all time. 

The success of this album helped make Katy Perry one of the biggest names in Pop music today.

One of the Boys is a result of years of hard work. Katy had recorded two solo albums (A) Katy Perry and Fingerprints that were cancelled by her record labels before this time and had written and recorded a large number of other songs. Most of the songs that made it on the OOTB track list are from those earlier projects.

This album mainly has more of an alternative pop/rock sound when compared to Katy's later albums and most of the songs are more raw sounding production wise. One of the hallmarks of this album is really the songwriting and lyrics which many fans from that era found to be more relatable than her newer music and Katy was far more involved in the writing and composition of her songs at the time than she is with her later music. Her older songs also have fewer writers as well in general. Thinking of You, One of the Boys and Mannequin are written and composed solely by Katy. 

Katy's album Witness has turned one year old and to celebrate Katy has sent all of us a handwritten card via Twitter.
​https://twitter.com/katyperry/status/1005300569076989955

You can see that Witness means so much to Katy that she took the time to write a handwritten card and share it with all of us. 

As part of the celebration Katy has released Dance With the Devil and Act My Age (which previously were bonus tracks on the Target edition of the CD and also the UK/Norway/Japan deluxe edition CDs.) everywhere music is streamed and sold.

Katy is at this time in the middle of the European Leg of her Witness : The Tour.