If you want to buy speakers for your computer system or headphones for your mobile, then definitely you want a nice sound quality in them. It is necessary to understand the terminology of the speakers before buying them. The more the Root Mean Square or RMS is, the better the sound quality is.
Hertz (HZ) is also the same type of word. We are able to hear more voices, and it depends on the frequency range of the speaker.
The woofer is a part of the speaker and it helps in hearing the low frequency range.
So keep all these facts or terminology in your mind when buying the speaker.