There are basically two types of compression methods: lossy and lossless. Lossy compression creates smaller files by discarding some information about the original image. Lossless compression, on the other hand, never discards any information about the original file. Lossless compression is preferred for archival purposes and often for medical imaging, technical drawings, clip art, etc. Lossy methods are especially suitable for natural images such as photographs in applications where minor loss of fidelity is acceptable to achieve a substantial reduction in bit rate. The lossy compression that produces imperceptible differences may be called visually lossless. Lossless compression compresses an image so when it is uncompressed as it is when you open it, its image quality matches the original source and nothing is lost. Although lossless compression sounds ideal, it doesn’t provide much compression so files remain quite large. For this reason, lossless compression is only used by the highest quality image formats. ImageConverter Plus supports both compression methods in a variety of image formats. Some formats supported, like PNG use only lossless compression. The most widely used JPEG is lossy, while others like RAW , TIFF, MNG may use either lossless or lossy methods.