"Edsger Dijkstra was a principal contributor in the late 1950s to the development of the ALGOL, a high level programming language which has become a model of clarity and mathematical rigor. He is one of the principal proponents of the science and art of programming languages in general, and has greatly contributed to our understanding of their structure, representation, and implementation. His fifteen years of publications extend from theoretical articles on graph theory to basic manuals, expository texts, and philosophical contemplations in the field of programming languages."
I think he may have borrowed that from the railroads, even if he didn't invent it independently though, he was smart enough to see its usefulness and apply it.
Crucially, this means C and C++, which means that Dijkstra's work is part of the foundation for most operating systems and low-level code in the world - indeed most software systems period, since the vast majority of these are somehow based on C.
The shortest path algorithm comes nowhere close to his other accomplishment. A significant part of computer science stands on its feet, because of the foundations he built.
Feel free to read one of the thirteen hundred things he published. Most relevant to you (probably) is that he championed the use of "structured programming" -- aka, if, for, while, and other narrowly focused constructs -- as opposed to GOTO: he's the author of "Go To Statement Considered Harmful ".
Also, remember also that many algorithms seem trivial once you've learned them.
He also spearheaded a compiler project which was made up of two teams where one part would check each other.
You should check out some of his work, in particular, his calling out computer manufacturers for making bogus hardware.
A paper describing THE: http://www.cs.virginia.edu/~zaher/classes/CS656/p341-dijkstr...
This paper here http://www.tomandmaria.com/tom/Writing/DijkstrasCrisis_Leide... has a worthwhile quote:
Dijkstra’s crisis was rather more idiosyncratic than has generally been acknowledged. He took up the language of crisis to convey the need to replace “Chinese armies” of badly trained and mediocre programmers with an elite corps of “mathematical engineers” modeled on himself.
Here is an article of personal reflections about a correspondence with Dijkstra: http://vanemden.wordpress.com/2008/05/06/i-remember-edsger-d....
Folks today don't seem to read much Dijkstra. I think the growing security industry is one side effect of that.