Arch-dependent
A ?Package is arch dependent if it needs to be build on each architecture individually. This will happen if it uses machine code, for instance if it is compiled from C code.
The buildds take care of building each package on all of the architectures.
If a package is not arch-dependent then it should be marked as arch-independent, to avoid the effort of rebuilding it for each architecture.
To mark a package as arch-dependent then the ?control file should contain
Architecture: any
unless the package is only for specific architectures. See architecture for more information on this.