Hardware is a very general term for equipment such made of iron and other “hard” material. Originally, it included tools, implements, and other items used in home life and activities such as gardening. Household hardware is typically sold in hardware stores. For a long time, it is also used for military equipment. Most of you use it for any kind of electronics, in particular for the physical components of computers such as main-board, mass storage, display, etc.
We use hardware for any physical component that is need to built a CAN network: Connectors, cables, semiconductors, etc. Additionally, we use hardware for any kind of devices and sub-systems that are connectable to CAN networks. This includes control units, host computer interfaces, human machine interfaces, gateways, I/O modules, actuators, and sensors.
The term component means for us any semiconductor (CAN transceiver chips, CAN stand-alone controller, or micro-controller with on-chip CAN module), and electrical (termination resistor) as well as electromechanical equipment (connector or cable) that is used to make a device. A device is a CAN connectable equipment, comprising the CAN interface hardware and additional application-specific hardware. In the automotive industry the CAN connectable devices are called ECU (electronic control unit). In the medical industry, a device is a complete system (e.g. computer-tomograph or lithotripter).
A sub-system is made by several devices featuring CAN connectivity. The sub-system itself may comprise a deeply embedded CAN network. Normally, most of the CAN networks are embedded, meaning that the end-user is not the system designer. If the end-user is the system designer, the CAN network is an open one. A system comprises several devices or sub-systems, which are connected to one or more CAN networks.