What's the difference between how and why?

First of all, express different meanings

1, how come: why; How is it possible ... (like that).

2. Why: (used in interrogative sentences) Why, why; (rhetorical question, indicating no need) why; The reason .....; Why (not); Why (expressing anger or annoyance); Reason, reason; Oh, honey.

Second, the usage is different.

1, where did it come from: it focuses on oral usage and does not appear in written language.

2, why: focus on universal questions, ready to use.

example sentence

1, how to do it? Coming? When the plane is about to take off, people must turn off their mobile phones and all electronic devices?

Why do people turn off their mobile phones and all electronic devices when the plane is about to take off?

2. how to do it? Coming? Are you a photographer?

How did you become a photographer?

3. Why? Do people paint?

Why do people paint?