Gas chromatography (GC) is a powerful analytical technique used for the separation and analysis of volatile compounds in complex mixtures. Developed by James and Martin in 1955, GC uses a mobile phase of inert gas, either solid or liquid stationary phases, and a variety of components to facilitate separation. The two main types, gas-solid chromatography (GSC) and gas–liquid chromatography (GLC), employ different stationary phases, influencing the separation principle—adsorption in GSC and partition in GLC. The key components of a GC system include the carrier gas, columns, temperature programmer, sample injector, detectors, and a recorder/read-out device. The separation process is influenced by factors like column length, diameter, and temperature, making GC a versatile tool for various applications. While offering high resolution and efficiency, GC has its advantages, such as prolonged column life, and disadvantages, like the potential for catalytic changes in sample components. Its applications span diverse fields, including environmental analysis, pharmaceuticals, and petrochemical industries. Understanding the principles, components, and influencing factors of GC is essential for optimizing its performance in analytical laboratories.