Embedded System
As its name suggests, Embedded means something that is attached to another thing. An embedded system can be thought of as a computer hardware system having software embedded in it. An embedded system can be an independent system or it can be a part of a large system. An embedded system is a microcontroller or microprocessor-based system which is designed to perform a specific task. For example, a fire alarm is an embedded system; it will sense only smoke.
RPI
Raspberry Pi (/paɪ/) is a series of small single-board computers developed in the United Kingdom by the Raspberry Pi Foundation in association with Broadcom.[15] The Raspberry Pi project originally leaned towards the promotion of teaching basic computer science in schools and in developing countries.[16][17][18] The original model became more popular than anticipated,[19] selling outside its target market for uses such as robotics. It is widely used in many areas, such as for weather monitoring,[20] because of its low cost, modularity, and open design. It is typically used by computer and electronic hobbyists, due to its adoption of HDMI and USB devices.
After the release of the second board type, the Raspberry Pi Foundation set up a new entity, named Raspberry Pi Trading, and installed Eben Upton as CEO, with the responsibility of developing technology.[21] The Foundation was rededicated as an educational charity for promoting the teaching of basic computer science in schools and developing countries.
Printed Circuit Board
A printed circuit board mechanically supports and electrically connects electrical or electronic components using conductive tracks, pads and other features etched from one or more sheet layers of copper laminated onto and/or between sheet layers of a non-conductive substrate.