Many cameras can save images in more than one format depending on their purpose. Some cameras use their own proprietary format to store images. Using a proprietary format will usually require an extra step to convert the image into one of the common formats like JPEG or TIFF before the image can be used. TIFF and JPEG formats are very commonly used in digital cameras. They are both compressed formats.
TIFF files are around one-third the size of the uncompressed image.
JPEG files can be compressed at varying rates. Many digital cameras will have several compression or quality settings. They may also combine a choice of compression and resolution. Most digital cameras come with software to edit and manage the image files created by the camera. The quality and usefulness of this software should be one of the factors you consider before making a purchasing decision.