Audacity

Qtractor is an Audio/MIDI multi-track sequencer application written in C++ with the Qt framework. Built for Linux and specially dedicated to the personal home studio.

Ardour is an open-source hard disk recorder and digital audio workstation, a collaborative effort of a worldwide team including musicians, programmers, and professional recording engineers.

MusE is a MIDI/Audio sequencer with recording and editing capabilities that aims to be a complete multitrack virtual studio for Linux.

Zrythm is a digital audio workstation designed to be featureful and easy to use. It allows limitless automation, supports LV2 plugins, works with the JACK audio backend, and provides chord assistance.

Rosegarden is a music composition and editing environment for Linux based around a MIDI sequencer that features a rich understanding of music notation and includes basic support for digital audio.

LMMS is a cross-platform software that allows you to create melodies and beats, synthesize and mix sounds, and arrange samples.

GarageBand is a fully equipped music creation studio right inside your Mac with a full sound library that includes instruments, presets for guitar and voice, and a great selection of session drummers and percussionists.