Each of the 9 applications on this site can be downloaded separately. It is more efficient to download them all at the same time. This is made possible by the « packaging » in Java: the Java compiler is unloaded only once at the same time as the 9 applications, and finally the place on the hard disk is of the same order of magnitude as for a single application (200 Megabytes typically). Under these conditions, the choice of the application is made once the program is downloaded, then executed, and not at the level of this site.