In an earlier question, I observed that grep is the most important fi lter, and I asked you to explain why it is especially useful in a pipeline. Considering your answer to that question, what is it...

In an earlier question, I observed that grep is the most important fi lter, and I asked you to explain why it is especially useful in a pipeline. Considering your answer to that question, what is it about the nature of human beings that makes grep seem so powerful and useful?