The equipment needed to produce music digitally varies. A musician with a home recording and production setup may have something as simple as a musical keyboard run through a computer and an 8- or 16-track digital recorder/mixing board. Others may have larger recording and mixing devices with a variety of digital special effects. A powerful computer with plenty of memory is essential for digital music production.
Numerous software products focus on digital audio production. Some is free, some is expensive. The software you use depends upon how seriously you take your music production. Pro Audio, Mixman, Mixpad, and Sonic are some choices. The software you choose depends largely on your budget, but if you're doing digital music production as a career, it's a good idea to invest in the best.
Whether you choose to use a fully featured recording studio, a simple soundproofed room or an office area, where you decide to do your work is important. If you do a lot of recording in the same room where you do your production work, consider a soundproof room or even a dedicated recording studio. An office is sufficient for your production work, so long as you have ample space for the equipment you use.
Mixing a song is one step in the process of music production, and while the way the instruments are mixed and equalized has a great impact on the sound of the overall recording, mastering is the final, definitive step in the process. While mastering is often confused with mixing, it is an entirely different process, and one that takes special skills. It's the step that comes before your music is packaged for sale. Many home producers leave mastering to professionals in a recording studio.
Like any artistic skill, digital music production is an art form that requires constant study and experimentation for improvement. Keeping up to date on the latest software and technology, as well as techniques, is crucial for the digital music producer. Many books on the subject can point you in the right direction, as well as online courses, both for a fee and free of charge (see Resources).