The Cockpit display systems (or CDS) provides the visible (and audible) portion of the Human Machine Interface (HMI) by which aircrew manage the modern Glass cockpit and thus interface with the aircraft avionics.
Improvements in computer technology, the need for enhancement of situational awareness in more complex environments, and the rapid growth of commercial air transportation, together with continued military competitiveness, led to increased levels of integration in the cockpit.
The average transport aircraft in the mid-1970s had more than one hundred cockpit instruments and controls, and the primary flight instruments were already crowded with indicators, crossbars, and symbols, and the growing number of cockpit elements were competing for cockpit space and pilot attention.
[1] Glass cockpits routinely include high-resolution multi-color displays (often LCD displays) that present information relating to the various aircraft systems (such as flight management) in an integrated way.
CDS software typically uses API code to integrate with the platform (such as OpenGL to access the graphics drivers for example).