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.
JBG is a graphic format for raster images, which is usually referred to as the Image JBIG 1-bit Raster file type. The purpose of the format is to store images - both black and white and color. Compared to other similar formats, it has a smaller file size. The .jbg file extension is related to the fact that the image is compressed without loss and is called JBIG. It was developed by the Joint Bi-level Image Experts Group. A .jbg file stores a 1-bit bitmap in JBIG graphic format. It is used as a standard for fax machines. JBIG is a lossless image compression standard. JBIG was developed primarily to compress facsimile images. However, it can be effectively applied to other classes of images. The format uses a variant of arithmetic compression, which is patented by IBM and known as Q-coder. A JBG file is a Jarnal background image. Jarnal is a cross-platform program that is written in Java for notes, thumbnails, and PDF annotations. It functions like a regular notebook with a small difference. It is believed that it can also be used as a stylus on a tablet.