What were the initial types of transistors referred to as?

The initial types of transistors were referred to as point contact transistors. This type of transistor was among the first to be developed and was created in 1947 by John Bardeen and Walter Brattain at Bell Labs. A point contact transistor utilizes a small piece of semiconductor material, typically germanium, with two closely spaced metal contacts. The way these contacts interact with the semiconductor allows for the amplification of electrical signals, demonstrating the fundamental operation of transistors.

Though other types of transistors, such as bipolar junction transistors and field effect transistors, have since been developed and are widely used, point contact transistors represent the very beginning of transistor technology. Integrated circuit transistors, while crucial in modern electronics, developed later when the concepts of point contact and bipolar transistors were already established. Understanding the history and evolution of these components highlights the significance of point contact transistors in the development of electronic devices.