An embedded operating system is a type of operating system that is embedded and specifically configured for a certain hardware configuration. Hardware that uses embedded operating systems is designed to be lightweight and compact, forsaking many other functions found in non-embedded computer systems in exchange for efficiency at resource usage. This means that they are made to do specific tasks and do them efficiently.
Embedded operating systems are also known as real-time operating systems (RTOS).
Embedded operating systems are usually used for hardware that have very little computing power, little RAM/ROM and a slow CPU, so they tend to be very specific in their applications and scope. They are usually made using assembly language in order to really take advantage of the limited computing resources, since it is the closest to machine language and is able to squeeze every drop of computing power available. This means that the OS is optimized for whatever hardware it was developed for and will not be compatible with other hardware systems with different configurations.
In most embedded OSs, the applications are built in to the OS or part of the OS, so they are loaded immediately when the OS starts. The most common examples of devices with an embedded OS would be cell phones before Android and iOS popularized the mobile operating system, which may still be considered as embedded but are also arguably desktop-like in the way they handle tasks and apps and their access to vast amounts of computing power. Embedded OSs can also be found in cars, large laser printers, some home appliances, and even military systems.
Notable embedded OSs currently in use by consumers include:
• Symbian - Used in cell phones, mainly ones made by Nokia
• Embedded Linux - Of which Android is a subset, used in many other devices like printers
• BlackBerry OS - For BlackBerry phones
• iOS - Subset of Mac OS X, used in Apple’s mobile devices
• Palm OS
• Windows Mobile
An embedded operating system is a specialized OS for use in the computers built into larger systems.
An embedded system is a computer that is part of a different kind of machine. Examples include computers in cars, traffic lights, digital televisions, ATMs, airplane controls, point of sale (POS) terminals, digital cameras, GPS navigation systems, elevators, digital media receivers and smart meters, among many other possibilities.
In contrast to an operating system for a general-purpose computer, an embedded operating system is typically quite limited in terms of function – depending on the device in question, the system may only run a single application. However, that single application is crucial to the device’s operation, so an embedded OS must be reliable and able to run with constraints on memory, size and processing power.