TGA is a long-used raster graphic format. It was developed by Truevision Inc. (now Pinnacle Systems) back in 1984. It was initially used by the developer only for its own graphic adapters, but gradually gained popularity (primarily in the field of video processing and animation). Widely used in computer games, where it is used to store textures (including 3D video games). The name of the format comes from Targa Graphic. TGA files may partially contain image transparency information. They can become the main one for creating GIFs.
BMP is a graphic format that allows you to store bitmaps as a bitmap based on single-layer rasters. It was developed by Microsoft. She also implemented it in the Windows operating system. The BMP format (English Bitmap Picture) is used in the work of many programs, since its support is integrated into Windows and OS / 2. Files of this format can have the extensions .bmp, .dib or .rle. The BMP graphics format has often changed. From the very beginning, the image structure was built by combining small squares, that is, pixels, each of which is capable of containing data about what color depth is. It happens to be 1, 2, 4, 8, 16, 24, 32, 48 bits per pixel. The size of the final image depends on the bitness. The BMP file format still looks like a monster, since it has large sizes. After all, the image is uncompressed, which can not be said, for example, about the JPG format. Any Windows operating system has the means to open such images. The main editing tool has always been Paint - the native Microsoft program that is in every version of Windows. In BMP, images are stored in their original form, but compression algorithms can also be used. Let's say BMP provides quality support for RLE compression.