Embedded systems can be summarized as a technological advancement. This advancement, in turn, attests to numerous avenues of improving human life. This work articulates in detail the components of the architectural framework embedded systems and explains their relevance to modern technology. Embedded systems architecture comprises of hardware and appropriate software that interfacing is done efficiently to meet the end requirements. This paper focuses on embedded systems in relation to their complexity and extensions, real time application, complexity based embedded system architectures which include FPGA based, SoC based, ASIC based, Microcontroller based and DSP based embedded systems. Furthermore, we evaluate their design parameters such as power, efficiency, reliability, security, and the complexity to compute their performance ratings. The research provides a review of trends in embedded architectures relevant to the current and upcoming phases of the development of embedded systems and their architectural characteristics, serving as a basis relevant to researchers and students of embedded systems and systems in general.