Raster graphics are digital images composed of pixels, while vector graphics use paths defined by points, lines, and curves. Common file formats include JPEG for photos, TIFF for professional photos, GIF for animations with a limited color palette, and BMP for lossless images. Vector formats include AI for logos, FLA for animations, and WMF for Windows logos. Compression reduces file sizes but can lower image quality, while optimization balances file size and quality for web viewing. Proper naming and organization of assets helps manage and locate graphics files.