The answer will depend on who you ask. For some people, turning 30 coincides with their first existential crisis. For others, it's the grand entrance to an exciting, new decade. For me, it was just another Saturday.

When I was younger, I loved birthdays. I always looked forward to becoming another year older and wiser -- and of course the gifts and celebrations were nice, too. At some point in my early 20s, I started focusing on where I was in life and where I was going, and I no longer saw the value of using an arbitrary day of the year as a marker of progress. I am who I am at a given moment, and being 28 or 31 or 64.5 years old doesn't change that. (On a somewhat related note, why wait until New Year's Day to set resolutions? Why not April 17th or October 3rd or today?)

I'm not a killjoy, however, and I do love celebrating birthdays and other milestones -- both my friends' and my own. It's always fun to get together and have a good time, whatever the excuse.

On a related note, my 85-year-old grandfather didn't care about birthdays until recently. During the past few years, however, he seems to relish birthdays more and more. For him, each passing year is a milestone that is really worth celebrating. Watching his attitude transform makes me wonder if my attitude might change again in the future, just like it did a few years ago.