If you aren't sure what the "-<x>" flag does for a particular command, but you are a competent Unix user, you should be fine with the man page or 10 seconds of

If you aren't sure what the "-<x>" flag does for a particular command, but you are a competent Unix user, you should be fine with the man page or 10 seconds of Google. If you aren't used to Unix, then I think it's dangerous to expect the verbose flags to explain things simply to you. For example, what would --mmap or --null-data mean to you in the context of the grep command? Are they immediately obvious?