Sound Processes is open source software. A graphical front-end or "desktop application" has been developed for Sound Processes, called ⬀Mellite, which is also open source under the GNU General Public License. Since a lot of work with Sound Processes will take place within Mellite, I often use their names interchangingly. I call Sound Processes a framework for experimental computer music and sound art, and I call Mellite an environment. It highlights the fact that you can write code using Sound Processes as a library, possibly selecting only a subset of its functionality, whereas Mellite is meant as a site in which one can structure compositions, and a workbench.
I sometimes abbreviate these two facets with SP and Mllt.