   Basic Stamp programming
  As I think I understand it - a programmer can write a program to a BASIC STAMP; which can then be used to control hardware devices, like on an autonomous robot.1 - What program compiles the code?  It couldn''t be a regular compiler like .NET?2 - Do stamps come with a USB cable for downloading the program?  If not how does it do so?3 - I once heard you could also (if clever enough) use a PDA to do the same activities as the stamp; and that it would even be more powerful.  How and why? 
  My understanding is that every Basic Stamp comes with its own code editor that will compile and upload the code to the stamp. Similarly, every Basic Stamp may have a different connector to the PC. AFAIK, both parallel and serial cables are used.As for using a PDA instead of a stamp, I can''t imagine that working well. A microcontroller needs relatively good timing, which doesn''t seem easy to achieve if you offload logic like that.  It''s more plausible to consider a PDA connected to an existing microcontroller rather than replacing the microcontroller. Of course, technology has suprised me before. ;  The Basic Stamp is a particular microcontroller. Answers to all your questions are here.