Some of the speakers on this list have simple analog connectivity options, but the majority offer some form of digital connection - that means you can plug them right into a computer's USB port. That said, this list highlights the best in the powered speaker arena - they have their own built-in amplifiers, which means they need to be plugged in. There are a multitude of PC speakers to choose from and you can certainly pair your PC with a Bluetooth speaker to augment the sound. Even a budget computer speaker can boost sound quality to such an extent that you'll be shocked by the poor quality of your laptop speaker. The good news - the market is completely saturated with computer speakers that offer quality sound. If you're looking to bypass your laptop speaker and take your audio experience to the next level, you should consider investing in a small or portable speaker to pick up the slack.
These built-in speakers aren't ideal for listening to music or watching videos - they can only play so loud and tend to be seriously lacking in the bass department. Laptops do have a small speaker or two with some sound output, but it's not exactly full, rich stereo sound.
When you buy a computer - whether it's a desktop or laptop - good sound is one of the things that's typically missing.