The magnifying glass represents one of the simplest, most direct applications of a converging lens. As light enters the lens, it becomes focused to a specific focal point in front of the center of the lens. Once you bring the magnifying glass to the optimal distance, so the focal point reaches the object, the object will appear at maximum magnification. Move the glass farther from the object and it will become distorted; move the glass closer to the object and it will decrease in magnification.
Divergent lenses are used on flashlights to magnify the light produced by the bulb. The light falls on the concave side of the lens, and the rays diverge on the other side, thereby increasing the apparent radius of the light source and providing a wider beam.