At work today, someone noted the word "how" was the odd one out among the typical question words. Who, what, where, when, why all start with W, but how is stuck with just an H.
I couldn't resist mentioning that how used to have a W too. In fact, all these words used to start with hw-.
But the old word "hwo" lost its W long ago, since the W pretty much blended with the O sound that came after it. And this "hwo" would eventually become "how".