A: 4K â also known as UHD (more on this in the next answer!) â is a picture technology that quadruples the number of pixels found in a full HD picture. These pixels are usually arranged in a 3,840 x 2,160 configuration, compared with the 1920x1080 you get in a full HD TV.
Files with the .7z extension are very similar to Zip files. These files are compressed archive files, usually created by the 7-Zip file archive utility. 7Z files can make it easier to send files and folders over email and the Web.
7-Zip is an open source file archiver, an application used primarily to compress files. 7-Zip uses its own 7z archive format, but can read and write several other archive formats. The program can be used from a command line interface, graphical user interface, or with a window-based shell integration. 7-Zip began in 1999 and is developed by Igor Pavlov.