You may have many of me but never enough. After the last one arrives you will have no more. What am I?

Answer: birthday

More What am I ? with answers

More What am I ?

You measure my life in hours and I serve you by expiring. I’m quick when I’m thin and slow when I’m fat. The wind is my enemy.
You need thousands of me to create a digital image. What am I?
You put me on a table and cut me, but you don't eat me. What am I?
You saw me where I could not be. Yet, often you see me. What am I?
You see me a lot, especially at night. I protect something special. Many shut me in fright. What am I?
You see me in the rainbows, you see me on Valentine’s Day, you see me in a busy street, and my blood turns this color when oxygen and I meet. What am I?
You shoot me but I don't die. You hang me but I don't die. What am I?
You take my clothes off when you put your clothes on. What am I?
You throw away my outside, you cook my inside. Then you eat my outside and you throw away my inside. What am I?
You throw me out when you use me and take me in when you are done. What am I?
You turn me over after you have traveled far. What am I?
You use a knife to slice my head and weep beside me when I am dead. What am I?