Programmable integrated circuits (IC) are electronic devices that can be programmed to perform a specific function. Many transistors, resistors, and other components are combined together in a certain way to perform a specific function.

Programmable ICs are used in many applications such as digital logic circuits, analog circuits, and mixed-signal circuits. It is often used in place of traditional discrete components such as transistors and resistors because they are more compact and easier to manufacture.

There are many types available, such as programmable ICs, programmable logic devices (PLD), field programmable gate matrices (FPGA), and complex programmable logic devices (CPLD). Each type of programmable IC performs a specific function and can be programmed to perform a variety of tasks.

Programmable ICs are usually programmed using a hardware description language (HDL) such as VHDL or Verilog. These languages allow to specify the desired function of the IC in a high-level, abstract way, which simplifies the design and debugging of circuits.