An ion is an atom or a molecule in which the total number of electrons is not equal to the total number of protons, giving the atom or molecule a net positive or negative electrical charge. Ions can be created, by either chemical or physical means, via ionization.

4DOS is a command line interpreter by JP Software, designed to replace the default command interpreter COMMAND.COM in DOS and Windows 95/98/SE/ME. The 4DOS family of programs are meant to replace the default command processor. 4OS2 and 4NT replace CMD.EXE in OS/2 and Windows NT respectively. 4DOS was written by Rex Conn and Tom Rawson; it was first released in 1989. These programs can also be initiated from the command line and/or called by scripts.

In physics and chemistry, an ion is an atom or group of atoms with a net electric charge.

The Ionians (; , Íones, singular , Íon) were one of the four major tribes that the Greeks considered themselves divided into, during the ancient period; alongside Dorians, Aeolians and Achaeans. The Ionian dialect was one of the three major linguistic divisions of the Hellenic world, together with the Dorian and Aeolian dialects.