While Unix (or your neighbor's dog) may not seem all that friendly at first, in a short time you will probably come around to appreciating its utility-if not its companionship. For example, Unix lets you customize commands for your own particular needs as well as choose how the system responds to just you. Furthermore, since Unix treats files, directories, hardware devices, and software all pretty much the same (as if they were files), you can connect terminals, printers, tape drives, etc., to your system without having to take a course in system programming, or look around for an expert.
Unix as a language has many elements. The shell, its outermost layer, interprets your commands as you interact with the system. Part of the power of Unix is that you can write your own shell or choose from a variety of available ones, all similar enough to still classify as Unix, yet different enough to confuse the unwary. The popular shells include the C shell (csh), the Borne shell (sh), and the Korn shell (ksh).
As a practicing scientist or engineer you may well have to work on a
number of computers, many with different Unix. This should not be a
problem-especially if you maintain somewhat of an experimental
attitude and just keep trying some variation of the command you want
the computer to obey. Eventually you may even make all environments
very similar and equally friendly by setting up aliases in your
.cshrc and .kshrc files.
We must admit, however, to having
otherwise dear colleagues for whom the change to Unix or from one Unix to another was
an emotion-laden, if not outright traumatic experience. To help
avoid stress, we give you some information to help you get
started.