In Victorian England, different flowers had certain meanings. This was called the "language of flowers," and a bouquet of flowers during this time was never just a bouquet of flowers. It was a message-- red roses for love (that one's still around, obviously, thanks to 1-800-FLOWERS), pansies for "I'm thinking of you," amaranth for immortal love (take that, red roses!), and so on.
Anyway, the reason I bring it up is because despite some real stretches of imagination with the language of flowers (a bouquet of oats to symbolize music, for example) the plain little daisy means innocence, cheer, and simplicity. Of course it does-- look at it! How could it be anything else?
So here's a daisy to bring a little cheer and simplicity to your day. Innocence? Well, I'll leave that up to you.