The PLT (Plotter) format is the best option when you plan to print maps, detailed building plans, banners, large posters or other types of line and curve drawings in full-color. Initially launched by Hewlett Packard for its own plotter printers, the PLT extension has now become an actual standard for almost all brands of cutting plotters.
PLT files can be created using AutoCAD and a few other types of computer-aided design software, or through conversion. They contain vector images which maintain their quality when scaled to different sizes and use the HPGL language. The main advantage of PLTs over PDFs, for example, is that they are designed particularly for plotter printers, which means you can send the large-scale graphics file directly to print.
PLT is an image format associated with plotters — a type of printing devices that use vector graphics as input files, as opposed to regular printers, which can only print raster images. Plotters can be of different kinds, including pen plotters — printing devices using a pen to draw lines and curves on paper, and cutting plotters — using knives to cut shapes into paper or other types of materials.
Files with the PLT extension usually store maps, posters, detailed designs of machines and other types of monochrome or full-colored graphics. PLTs can be created using computer-aided design software, such as AutoCAD and Adobe Illustrator. Or they can be obtained via conversion from other image formats. The main advantage of PLT over other graphics extensions is that the image can be sent directly to the plotting device.