There are different kinds of files for different types of images. Using the right type of image can be important. Here are the three main types of image you'll find on the web:

• JPEG, with the file extension .jpg or .jpeg. JPEGs are designed for photographic images: they support a large number of colors and the file sizes are kept small by compression. The downside is that compression can make images look fuzzy, particularly when zoomed in.
• PNG, with the file extension .png. These take up more space than JPEGs, but do not use compression and will look sharp even when zoomed in. As a result, they're the best choice for things like line drawings, logos, diagrams, and charts. PNGs support fewer colors than JPEGs, so they’re not as good for photographs.
• GIF, with the file extension .gif. The main benefit of the GIF format is that it can be used to create animated images, which can then be added to a web page like any other picture. Much like PNGs, they are also useful for simpler images with fewer colors.