The NEXT macro and terrible use of the stack is kind of integral to threaded code.  I&#x27;ll let you read the tutorial to find out why :-)<p>In general you shouldn&#x27;t expect FORTH to be fast -- it uses the stack far too much and the way it does branching kills branch prediction on modern CPUs.<p>However it is very small and a lot of fun to write.  If you are looking for a system that can run on baremetal and where you can <i>completely</i> understand the system from top to bottom, then that&#x27;s FORTH for you.<p>Compared to C, FORTH has an extensible syntax and features like exceptions.  Compared to FORTH, C is a lot easier to write significant programs in.