how 
(hou)
(hou)adv.
1. In what manner or way; by what means: How does this machine work?
2. In what state or condition: How is she today?
3. To what extent, amount, or degree: How bad was it?
4. For what reason or purpose; why: How is it that he left early?
5. With what meaning: How should I take that remark?
6. By what name: How is she called?
7. By what measure; in what units: How do you sell this corn?
8. What. Usually used in requesting that something be said again: How's that again?
9. Used as an intensive: How we laughed!
conj.
1. The manner or way in which: forgot how it was done.
2. That: I told them how I had once been bitten by a snake.
3. In whatever way or manner; however: Cook it how you please.
n.
Idioms: A manner or method of doing something: "The how of research is generated by the why of the world" (Frederick Turner).
and how Informal
Most certainly; you bet: She's a good dancer, and how!
how about
1. Used to make a suggestion or to offer something: How about a cup of tea?
2. Used to request an opinion about something considered remarkable or impressive: How about that storm last night?
how about that Informal
Used rhetorically to express surprise or wonder at or approval for something.
how come Informal
How is it that; why: How come you're so late?
how so
How is it so: You say the answer is wrong. How so?
[Middle English howe, from Old English hū; see kwo- in the Appendix of Indo-European roots.]