句点

[Dr. Love]

So, my friend and I have been arguing about this.
Do you need a period when you ask a question?
He says no, I say yes.
Your insight would be appreciated.
Yours,
Will

[NileCat]

1. Before Western culture was imported, we didn’t have the question mark "?".
2. In the proper grammar, every sentence should end with a period "。".

So, you can end your question sentence with a period or a question mark today. But a proper sentence requires one of them.
元気ですか？ (many people use "?" today)
元気ですか。 (would seem more polite/proper/traditional)
However, you can omit the period in titles, in captions, or in short messages, like you do in English.
元気ですか

Hope it helps.