A camera is a device for taking photos or videos. With such an instrument, you capture light: The sun or a lamp emits light that falls on an object. This light is reflected, thrown back. When this light enters a camera, it creates an image.
In the past, there was an empty plastic strip in a camera. The image was formed on this strip. From the plastic strip you could then take the real photos. This was called an "analogue" camera. In modern cameras there is no film strip. The picture is stored electronically. These are called "digital" cameras or "digital cameras".
If you take still pictures with the camera, it is a still camera or a camera. If you make videos with it, i.e. pictures that move, it is called a film camera or video camera. However, today there are also many cameras with which you can also film videos.
The word camera comes from the Italian language: "camera" means chamber or room. The first cameras were actually not much more than a box with a hole in the wall. Today, such a box would be called a pinhole camera.