IBM 5250, originally, was a particular model of a terminal device sold with the IBM System/34 minicomputer system. Similar to the IBM 3270, it is a block-oriented terminal protocol, yet is incompatible with the 3270 standard. The relationship between the terminal and system was rich: The system sent a data stream containing markup bytes indicating the boundaries of data entry fields, highlighted or colored areas, and indication that the system was busy responding to the last request from the terminal. The 5250 data stream definition has been refined over time to include GUI elements like pop-up windowing, check and option boxes, mouse handling, and pull-down menus. A computer terminal is an electronic or electromechanical hardware device that is used for entering data into, and displaying data from, a computer or a computing system. ... For other uses, see IBM (disambiguation) and Big Blue. ... The System/34 was a minicomputer marketed by IBM from 1978 to 1983. ... Minicomputer (colloquially, mini) is a largely obsolete term for a class of multi-user computers which make up the middle range of the computing spectrum, in between the largest multi-user systems (traditionally, mainframe computers) and the smallest single-user systems (microcomputers or personal computers). ... Clemson Universitys library catalog displayed in a 3270 emulation program The IBM 3270 is a class of terminals made by IBM since 1972 (known as display devices) normally used to communicate with IBM mainframes. ... A block-oriented terminal is a type of computer terminal that communicates with its host in blocks usually consisting of chunks of text, as contrasted with a character-oriented terminal that communicates with its host one character at a time. ... GUI can refer to the following: GUI is short for graphical user interface, a term used to describe a type of interface in computing. ...

The term "5250" now refers to the content of the data stream itself; few physical 5250 terminals still exist, although they are still used to provide a "connection of last resort," hard-wired to the host computer. Robustly constructed, 5250 terminals weighed roughly 36kg (80 lbs.) The 5250 terminals generated an audible clicking sound as the user typed, similar to the electric typewriters of the era. Today, it is more common to use PC or web-based terminal emulation packages that can interpret and display 5250 data streams. Commonly used emulators are IBM's own iSeries Access,TN5250, an open source project, WRQ's Reflection, Cybele Software's z/Scope Express 5250 and Hummingbird's Host Explorer. i5 Model 570 (2006) The IBM System i (formerly known as iSeries, AS/400, and Application System/400) is a minicomputer platform produced by IBM. It was officially introduced as the AS/400 in 1988. ... Open source refers to projects that are open to the public and which draw on other projects that are freely available to the general public. ... WRQ, Inc. ... For other uses, see Hummingbird (disambiguation). ...

A number of modern 5250 emulaton packages include additional features beyond displaying the data stream; for example, IBM's iSeries Access includes support for graphical system administration, remote system console connectivity, file transfers, macros, printer emulation, and support for client-server database connectivity.Examples of these would include Psion's Teklogix radio data terminal or its counterpart, LXE terminals. Psion PLC is a consumer hardware company mostly known for developing the Psion Organiser as well as a whole range of more advanced, clamshell-design Personal Digital Assistants. ... It has been suggested that dumb terminal be merged into this article or section. ...

External links

• "System i Access"
• "FTP software repository at IBM"
• TN5250
• 5250 emulator written in Java
• another 5250 emulator written in Java
• Mocha TN5250 for a number of different Operating Systems from MochaSoft
• z/Scope Express 5250 from Cybele Software Inc