Embedded Glossary

QML (Qt Modeling Language) is a declarative language for designing graphical user interfaces within the Qt framework. Rather than specifying every step, it describes an interface through individual elements, their arrangement and their behaviour. Animations, states and user input can be expressed concisely and clearly. QML typically connects to C++ for the underlying logic, separating presentation from functionality. In embedded systems, it is particularly suitable for HMIs on more capable devices running Embedded Linux that require a fluid, touch-operated GUI. This separation simplifies maintenance and later extensions.

Qt is a comprehensive framework for cross-platform applications that combines graphical user interfaces with building blocks for networking, data management and concurrent processing. The core language is C++, which provides access to the individual functional areas. The interface itself can additionally be described in the declarative language QML, which allows presentation and application logic to be kept apart. In an embedded context, Qt is particularly suited to more capable devices running Embedded Linux, on which it supports demanding, touch-operated displays together with the underlying logic of a modern HMI. For resource-constrained targets, reduced variants such as Qt Quick Ultralite are available, limiting the scope to the essentials.