PM, SDE and SDET

It's been a fast week, working on the Vista Test Pass.  I was browsing through today's blogs when I saw an entry by my recruiter, Julia Colvin, that talked about moving between positions at Microsoft, more specifically between the three disciplines of PM, SDE and SDET.  Not too long ago, I thought PM having the word 'manager' in it denotes a higher-level position, and I wondered how a college applicant could apply for it.  I found out it was just one of the three disciplines of program management, development and test, and their respective positions are as follows (in brief words): 

-  PM (Program Manager): designing specifications, features and product goals, also customer interaction

-  SDE (Software Design Engineer): coding and developing features for specific products

- SDET (Software Design Engineer in Test): driving product robustness through designing, developing and optimizing automated tests

These disciplines do overlap and actually have much in common.  I like to think of it as three circles forming a triangle, with all three overlapping in the middle.