Here's one short, really annoyingly hard-to-find command:

ln

The 'ln' command is used to create a symbolic link to another file or directory. The closest thing Windows NT has to it is creating a desktop shortcut to a file or directory. However, 'ln' has a bit more power (I won't go into that part, just type 'man ln' to learn more)

That's all pretty simple, and I can tell that all you experienced Linux people are shaking their heads at this and saying "Like, duh, ya big moron..."

Here's why I am putting this here:

• Get any doc/web page/whatever about how to compile/recompile the Linux kernel. Note that they ALWAYS mention creating a Symbolic Link to a Linuzxxx directory, so that you can then change back to the old if you screw up the compile.

• Get your little install book that came with your Linux install (If you bought it at a store)

• Get a big fat book on Linux. (I went out and bought RedHat Linux: Unleashed)

Note that they ALL talk about Symbolic Links as if they're no big deal and everyone has them (Right next to their opinion, right?)... Also note that there is NOWHERE that tells you how to make a damn Symbolic Link!!! It'll tell you about why you would make one, and where you would make one, but never HOW you would make one! (Linux authors take note of that!!)

RH Linux: Unleashed - It's pathetically hilarious about this (I gotta tell ya about this one...)

OK, in the Index in the back of the book (Always a great place to go in any technical book) it lists Symbolic Link, says see page 643. Cool, so I flip to page 643. This drops me in the Glossary. It has the entry Link, Symbolic. It says:

Directory entry that provides an alias to another file that can be in another filesystem. Multiple entries appear in the directory for one physical file without replication of the contents. Implemented through link files; see also link file.

I look at Link File. It says:

File used to implement a symbolic link producing an alias on one filesystem for a file on another. The file contains only the fully qualified filename of the original (linked-to) file.

There is also an entry for "Link, Soft" which says to see "Link, Symbolic"... (Great help there... Not!)

Nowhere in the whole darn book does it mention that 'ln' is used to actually create these darn link files!  After learning from finally asking someone else about how to create a symbolic link, I finally find "ln" at least listed under "File Utilities" on page 352, but that's it. Only a list of the file utility commands (such as ln, cp, rm, mkdir, etc). However, it is NEVER defined.

For lack of this little command, it's very hard to do much advanced stuff in Linux. It kinda reminds me of that story about "for lack of a nail, the kingdom fell"

Oh well, hope this helps somebody out there! :)