Music has been an instrument for human kind to achieve multiple outcomes: Express your feelings, call to action, tell a story...
Another use that I'm sure a lot of people give to music, but perhaps not often recognize it as such is that of using music as an instrument to achieve focus. This could be for example while working on homework that required deep concentration.
Personally, I myself got my start of this habit back when I was in grade school. I can particularly remember that the very first volume of Pure Moods as being my intro to developing a test for music to helps me focus. I can still listen to this album and it brings back a lot of good memories :)
As I have progressed through college, then graduate school and now at work (in the office), this habit has continued through the years and I've come to develop an evolved and fine tuned taste for the music that helps me achieve a state of deep focus.
For me, it has not always been one specific genre of music that defines this category. It has actually evolved through the years, starting with New Agey type of music (exemplified by the Pure Moods album) and now it appears I have settled on some sort of mix between Deep House and Chill Electronic that is best exemplified by AK's music.
I started paying more attention to this habit recently after having read Cal Newport's book Deep Work. And I even created a Spotify playlist inspired by the book with the intent of always reminding myself the importance of achieving deep levels of focus while at work in order to be able to create more meaningful contributions through my work.
I'm looking forward to observing how my taste for this type of music continues to evolve.