We’ve already talked about the way spells are casted and channeled through a wand, but there’s still much room to discuss magic in the Harry Potter universe. A wand’s power is amplified by the caster’s ability to perform magic, but in case of the broom, its quality and the spells a wizard casts on it are what really determines how effective they are.
In fact, most modern brooms come with a de-facto power once bought by a wizard. In older times, wizard themselves were responsible for enchanting their brooms, as they were often used as a means of transportation that could be easily concealed from muggles. In fact, the first brooms used to fly were no different from those used to swipe floors.
It was only in recent wizard history that brooms started to become more and more specialized; even more so after the invention of the cushioning charm, which removed the uncomfortable factor from riding in one of these tools.
Originally, wizards had to enchant their regular brooms, which could then be used as a means to travel. As the years went by, magical craftsmen started to mass-produce brooms specially designed to fly; these felt more comfortable to the rider. They were also more aerodynamic than regular brooms.
This new brooms are used by wizards not only as transport, but also as the official rides of Quidditch. Although they are able to fly on their own (without needing the wizard to cast direct spells on them), mages often cast command spells to make them turn, go up and fall down with ease.
Some wizards even believe that they brooms develop some sort of basic personality, because they seem able to understand commands without the need of casting spells. In any case, brooms are one of the many resources used by wizards to hide themselves from muggles – and they certainly come in handy in many situations!