Ms. Reinze Vito welcomes the viewer to her online classroom and provides her email for contact. The document then defines key computer terms and describes the basic components and functions of a computer system, including hardware like the system unit, peripherals for input, output, and storage, as well as software like operating systems and applications. It explains that hardware is the physical equipment, software is instructions that tell the computer how to work, operating systems support basic functions, and applications perform specific tasks for the user.