The 3270 Information Display System (a Dumb Terminal), a product from IBM, was, prior to the arrival of the PC, the way that almost the entire corporate world interfaced with a computer. When first produced (the early 1970s), a 3270 display terminal was considered a vast improvement over its predecessor, the 2260.

The terminal was a non-graphical (text only) monochrome (black screen with green letters aka Green Screen) display that buffered data so that key strokes could be saved until the ENTER key was pressed.

Today, the 3270 is emulated in most Terminal Emulation (TE) software packages along with VT and 5250.