Bullet cameras range in size from a rifle bullet or a lipstick tube to a bread loaf, but the basic gist is the same in every case. They’re linear security cameras that mount to your wall or ceiling with a tri-axis mount (so don’t worry about orienting them while you’re screwing them into the wall) and focus on a specific part of your premises. Given their tubular design, they have room for night-vision and IR features, and they have better range and zoom capabilities than the flatter dome security cameras.
Since they’re so obviously recognizable as a security camera, they’re a great deterrent as well, and they’re easy to mount just about anywhere. With the typical weatherproof hoods, they’re quite durable, but they don’t always come with the full IP certification of other models.
On the other hand, they’re more susceptible to damage than other models and they make tempting nests for wildlife, so make sure you choose a good spot to install bullet cameras on your premises.