Integrated circuits (ICs) are semiconductor devices that integrate an entire circuit on a single silicon wafer, commonly referred to as "chips." They serve a wide range of functions, from simple logic gates to complex microprocessors, and are ubiquitous in modern electronics. Early examples of ICs include linear amplifiers and TTL series digital NAND gates from the late 1960s, with significant milestones like the HP-35 pocket calculator emerging in the 1970s. The discussion highlights the evolution of logic circuits, noting the transition from resistor-transistor logic (RTL) and diode-transistor logic (DTL) to transistor-transistor logic (TTL). Understanding the history and functionality of ICs is essential for grasping their impact on technology today.