Digital marketing is the marketing of products or services using digital technologies, mainly on the Internet, but also including mobile phones, display advertising.
Information technology (IT) is the use of computers to store, retrieve, transmit, and manipulate data, or information, often in the context of a business or other enterprise.
Computer science is the study of the theory, experimentation, and engineering that form the basis for the design and use of computers.
A network connects computers, mobile phones, peripherals, and even IoT devices. Switches, routers, and wireless access points are the essential networking basics.
Electrical engineering is a professional engineering discipline that generally deals with the study and application of electricity, electronics, and electromagnetism.
Mechanical Engineering is the discipline that applies engineering, physics, and materials science principles to design, analyze, manufacture, and maintain mechanical systems.