What is Creativity?

I found this on some website about creativity.  For years I thought I wasn’t creative or an artist.  My sister was a visual artist.  She could draw, paint, whatever.  I was awful at all of the typical “art” mediums.  I found my inner artist for years thinking I should just be a math nerd and some kind of business woman since I’m not creative.  What is art anyway?
Since music is such a huge part of my life, for years I wished I could write and play music, but no such luck.
As pathetic as it is, it took me many years to realize that writing is a form of creativity.  I’ve given up fighting with myself.  I am a writer.  On my better days I’m creative.  I may never be a considered a good writer or write anything of significance, but I am a writer. I am creative.  Writing makes me feel sane and alive.  
What makes you feel alive and fulfilled?