Sound design — is the process of creating, modifying, or manipulating audio elements to achieve a desired sound.
For us music producers, sound design is primarily about synthesizing sounds and working with samples. When you’re just starting out, it’s best to focus on mastering one synthesizer in depth. Once you understand how it works, learning other instruments becomes much easier — you’ll just need to adapt to a different interface.
Oscillator — a waveform generator that serves as the sound source in a synthesizer.

Most popular waves:
There are also wavetable synthesizers, which can handle more complex waveforms — ones that can literally take on almost any shape.
Envelope — a curve that describes how a sound evolves over time.
It has 4 components:
Attack - the time it takes for the sound to reach its maximum level after a key is pressed or the sound is triggered.
Decay - the time it takes for the sound to drop from its peak level down to the sustain level.
Sustain - the volume level that is maintained after the decay phase, as long as the key is held.
Release - the time it takes for the sound to fade out after the key is released.

Amplitude — the loudness of an audio signal.
Modulation — the automation of sound parameters using LFOs, envelopes, or other sources.
LFO (Low-Frequency Oscillator) — a low-frequency oscillator used to modulate sound parameters.
Filter — a tool that shapes sound by cutting or boosting certain frequencies.
Frequency — determines the pitch of a sound, measured in hertz (Hz).