Finding celestial objects is much easier with a finder compared to using a telescope alone. The reason for this is the telescope's small field of view. The finder shows a larger section of the sky, making orientation easier.
There are two types finder:
optical finders are small telescopes with a large field of view. They show an enlarged image.
Red dot finders or projection finders are sighting devices with a LED light. They use a light point to mark the direction in which the telescope is aligned. Their image is not enlarged, but on the other hand they cover the largest possible area of the sky.