vST

VST stands for Virtual Studio Technology, a software interface for integrating virtual instruments and effects into digital audio workstations. Developed by Steinberg Media Technologies and released in 1996, VST has become one of the most widely used plugin standards in computer music. Plugins based on VST run inside a host DAW, which handles audio I/O, MIDI, and automation, while the plugin performs DSP tasks.

There are two main categories: VST instruments (VSTi), which generate audio via synthesis or sampling, and VST effects (VSTfx), which process existing audio. Some plugins offer both capabilities or host multiple modules.

Format and evolution: The VST standard has evolved from VST2 to VST3. VST2 remains common in older software, but Steinberg and many developers have shifted toward VST3, which introduces features such as improved parameter handling, sidechaining, tempo-sync, and better host communication. VST3 also allows dynamic loading and better CPU efficiency in some hosts.

Usage: In practice a user loads a VST plugin into a DAW, selects it as a track's input or effect insert, and uses its GUI to adjust parameters, route MIDI or audio signals, and automate controls. VST plugins have enabled the proliferation of virtual instruments, amp simulators, reverb, compression, equalization, and specialized processors.

Alternatives: Other plugin formats exist, such as Apple's Audio Units and AAX for Pro Tools, as well as open formats like LADSPA and LV2, but VST remains a dominant standard in many production environments.