... 2000¹

Revised October, 2001

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... GNU/Linux²

See Section 1.2 for a short discussion of naming.

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... individuals.³

The latter is an increasingly pertinent issue as the movie and recording industries seek to strengthen their control of digital content, but falls outside the scope of this note.

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... card⁴

Like index cards, these boards come in a range of sizes.

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... needed.⁵

In Windows, drivers are part of ``dynamically linked libraries'', and can be modified by installation of unrelated software. This is the primary reason Windows becomes less stable as more software and more drivers are installed.

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... keyboard,⁶

Even if you are a fast typist, the CPU cycles millions of times between keystrokes.

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... kernel⁷

Or kernels, if there is more than one OS on the machine; this information is determined by the specific installation and therefore cannot be hard-coded, which is why the BIOS does not load the kernel directly.

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... CD-ROM).⁸

The default BIOS behavior is to check the floppy drive for a disk when the power is turned on, and attempt to boot from the floppy if one is present. If the floppy is not bootable, the BIOS prints an error message such as ``Non-system disk; remove disk and hit any key.''

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... drive.⁹

The final chicken-and-egg question is, ``Where did the boot floppy come from?'' The first operating systems were loaded by hand, either with actual switches, or with punch cards. In typical bootstrapping fashion, once you have a running operating system, you can use it to write more complicated operating systems, and to save them in bootable form. Computer science is permeated with recursive solutions like this. Compilers, the programs that ``translate'' human-readable computer programs into machine-readable binary executables, are another example. After all, a compiler is itself a program, so it must have been compiled...

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... handle,¹⁰

Almost always because the programmer did not account for some contingency.

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... crashes.¹¹

The symptom of a Windows crash is BSOD--the Blue Screen of Death.

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... code.¹²

Melissa, the ``I Love You'' worm, Sircam, and Nimda have demonstrated the cost of integrating user applications (such as email clients that automatically run executable files they receive) with system functions in a low-security environment.

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... rare.¹³

The most common causes are hardware defects and malicious attacks.

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... GNU/Linux.¹⁴

In Windows 9x, these features were added after the OS was written. The result barely prevents users from reading each others' files, and is completely insecure in a business environment, or if the computer is connected to a network. Home users are only now becoming aware that their DSL connections potentially allow anyone in the world free access to their hard drives.

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... files).¹⁵

No responsible administrator would remove outdated files this way.

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... capability.¹⁶

Not only is the hood welded shut, but the doors have no locks, and the ignition is a ``start'' button!

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... certainty.¹⁷

Whether or not anyone actually reads or deletes your files is another matter, but if you're permanently offering the world the opportunity, sooner or later it will happen.

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... everything¹⁸

Be it an ordinary file, a directory, a hardware device (like the hard drive, sound card, or mouse), or any of various esoteric gadgets used for normal operation.

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... drivers.¹⁹

The hardware manufacturer must release detailed technical specs--which are trade secrets--in order for a programmer to write a driver. Not all hardware manufacturers are willing to release proprietary data to a loose association of volunteers.

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... server.²⁰

Your web browser handles the details; all you see is http://mathcs.holycross.edu in your Netscape location bar.

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... query,²¹

This data routinely includes the user names of anyone logged on to your computer, the name and version of your operating system, and the network services your computer is offering.

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... beginner.²²

Use judgment; an unhelpful question like, ``My CD-player doesn't work. What's wrong?'' is likely to garner some annoyance. People are always more helpful if it's clear you've tried obvious channels like reading the manual page before posting.

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... obtained.²³

Searching for more evil than Satan himself returns, as its number-one choice, the Microsoft web site.

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... wrong.²⁴

You can safely run make several times, but should not need to. For some software, the Makefile must be edited by hand, and you may not discover this until the first run of make fails to compile an executable binary.

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