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Intensity - Strength level

Enhanced Definition

In the context of IBM mainframe systems and 3270 terminals, "intensity" primarily refers to a **display attribute** that controls the brightness or prominence of characters on the screen. It is used by applications to visually differentiate or highlight specific fields, messages, or data elements, effectively conveying a "strength level" of visual emphasis to the user.

Key Characteristics

- Two Primary Levels: Typically, 3270 terminals support two distinct intensity levels: normal (standard brightness) and high or bright (increased brightness). The actual visual difference can vary slightly between physical terminals and emulators.
- Application Controlled: The intensity attribute for specific screen areas or characters is set by the mainframe application program (e.g., COBOL, PL/I, Assembler) or through screen mapping facilities like CICS BMS (Basic Mapping Support) or IMS MFS (Message Format Service).
- Part of 3270 Data Stream: Intensity is encoded as an attribute byte within the 3270 data stream sent from the mainframe to the terminal or emulator, instructing it how to render