VHDL is an integrated circuit programming language primarily used on Field Programmable Gate Array (FPGA). It's being used to develop circuit and logic systems at far greater flexibility than in-house Integrated Circuit. It's ideal for small to medium-scaled projects in which it would be more cost-effective to use an existing circuit that's programmable instead of building a new circuit from scratch.
Although I don't expect to write VHDL again, this is just a reflection of my exposure to programming a circuit.