The VT520 is like having four terminals in one. You can create four independent sessions over a single wire with SSU (Session Support Utility) or you can access applications via the three connectors provided on the terminal. For example, with the VT520, a telemarketing sales representative talking on the telephone can easily flip from a stock status application to a customer profile report to an order-entry system to a credit and collection report.

The VT520 offers other multi-session features such as split-screen viewing of any two sessions, labeling of each session, session status indicators, as well as copy and paste within and between connected sessions. Although the sessions are independent, you can use common features like setup, review previous lines, define key editor, and page memory allocation, to name a few.

The VT520 is compatible with more than 30 operating systems, including VMS, OpenVMS, UNIX, PICK, MUMPS, and Multi-user DOS. Included are 17 terminal emulations, such as Digital, Wyse, TeleVideo, and ADDS.