The meaning of the Acronym IO is...

IO is

• Illuminati Online
• Internex Online

More Meanings For IO:

• Images Only
• CPIO Compressed file archive
• Object file (Modula-3)
• Input/Output
• Initial Object
• In Order ....
• In Our
• Instance Of
• Inter-Office
• Intellect Optional
• Interacting Object
• Interaction Objects
• Infinitely Often
• Interpolate Once
• Indian Ocean

IO is also in:

• Astronomy
• Chat
• Databases
• File Extensions
• General
• Mathematics
• Ocean Science
• SMS
• Software
• Telecom