4K (computer virus)
4k is a computer virus which infects COM files and EXE files. The virus was one of the first to employ stealth tactics. Infected systems will hang, after September 22 every year, which is also the date of birth Bilbo Baggins, a character from "The Lord of the Rings". The code was intended to display the message "Frodo Lives", but hangs in all known variants.
Display aspect ratio
Since 2011, several monitors complying with the Digital Cinema Initiatives 4K standard have been produced. The standard specifies a resolution of 4096×2160 and an aspect ratio of almost 1.9:1.