How are different kinds of programming libraries built. Such as PHP ImageMagick, CURL, or JQUERY
I'm curious to know how different kind of libraries are built. Such as the PHP ImageMagick, Curl, or the Java script JQUERY, PROTOTYPE. What is the source build of these libraries. Is it C++ or their native. 
How are different kinds of programming libraries built. Such as PHP ImageMagick, CURL, or JQUERY
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I'm curious to know how different kind of libraries are built. Such as the PHP ImageMagick, Curl, or the Java script JQUERY, PROTOTYPE. What is the source build of these libraries. Is it C++ or their native. 