Tracker INIT is a generic antivirus suspicious behaviour blocker, something like Gatekeeper or SAM Intercept "lite". It is not as sophisticated as either of the later ones, but it gets the job done, quickly and easily. Tracker needs a 68020 processor or greater. It will not run on old 68000 Macintoshes. It will run fine on any PowerPC machine. It also needs at least System version 7.0.0.