in reply to What language should I learn?

This is just too broad/vague a question. It is like going to college and, without providing any information about yourself, your interests, and your prospects, blindly asking what your major should be in. If this is how you approach things in life you are simply asking for failure.

What tool you use has everything to do with what you are trying to accomplish. Different tools are useful for different problems and computing is no different. You must start with a class of problems and spend time, energy, and thought power toward learning popular and effective solutions (if they exist) to that problem. For instance, if you were a statistician and the only language you knew was the one for the R system you would likely be employable. I once worked with a developer whose only language was assembly, but he was creating advanced embedded control systems for computerized high-end telescopes and exceedingly happy doing so. Choose the right tool for the right job.

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