Cooperation

What do computer programmers do? What programmers mostly do (or should) is cooperate, and try to reuse existing work instead of doing it over. The Web itself is a fine example of this. Lots of programs cooperate to let you read this page.
Editor
How I wrote the page, and later made changes to it. I didn't have to use the same editor each time, because this page is written in a portable standard form.
Server
Where the page is stored so that people can request it.
Router
How your browser request located the server, and how the server got the results back to the browser.
Browser
How you finally view the page. Again, any browser should work, because this page is written in a portable standard form.
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