What types of Linux skills does a typical PHP developer need?
I am trying to improve my programming skills by learning more about frameworks, methodologies, and related technologies. I have seen a lot of job postings with requirements that also include Linux and/or Apache. So, my question is, what sort of things should I study in terms of Linux from a development standpoint? 
What types of Linux skills does a typical PHP developer need?
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I am trying to improve my programming skills by learning more about frameworks, methodologies, and related technologies. I have seen a lot of job postings with requirements that also include Linux and/or Apache. So, my question is, what sort of things should I study in terms of Linux from a development standpoint? 