".newsrc" files contain information about groups you subscribe and articles already seen. These files are used by all major news readers (XNews, Mozilla, SLRN, Tin, Gnus, Forte Agent), and because of their small size and good compression potential, they may be easily moved on a floppy or flash drive and used between two or more machines (and even clients). If you set a path to a file in news server settings, program immediately updates time each time you read another message. Group index is synchronized with file contents every index reload.