A few things can be stated. First, this is Mandarin Chinese and it is also called Putong hua. This is important to point out, because there are so many dialects in Chinese. Remember there are over one billion Chinese!
Second, it literally means you well? So, it is an interrogative, that is, it expects a response. Third, it is singular, that is, only one person is in view. We do not differentiate second person singular and plural in English, but in Chinese you certainly can. If we said, "nimen hao ma," then this would mean - Are you all well?
Fourth, this is used as a greeting and it is probably the most common greeting in China. You can use this statement any time of the day on almost any occasion. Good luck with further Chinese learning. In the future and even now, it will be one of the most important languages to learn.
"How are you?"
你 好 吗 ( Ni Hao Ma) This literally translated means Ni= you Hao= good Ma= question in Mandarin Chinese. Since the Chinese speak in tones it can be easily confusing if you just said Ni Hao like you would in English and made the hao in a higher tone because they you would be changing the meaning of the sentence so instead in Chinese they speak the question mark (the way I think of it haha).
To this question you answer back 我 很 好(Wo Hen Hao) which translates to I (am) very good.
It means how are you ( 你好吗）