This section is missing stuff like setuid, sticky bit, extended attributes, etc. (SELinux stuff and setgid? I'm not sure if there's more.) For example, `ls -ld /tmp` shows `drwxrwxrwt`, `ls -l /bin/sudo` shows `-rwsr-xr-x`.
> History Expansion
To this section, it might be good to add `!$`. Also maybe a quick overview on word designators, to cover syntax like `!:^`, `!:2`, `!:<asterisk>`, etc. There's also modifiers, like `!$:h` to return the (h)ead of a path that's the last argument of the previous command, etc.
> Bash Globbing
> @ Matches exactly one of a given pattern
It might be better to put these extended glob ones as @(pattern-list) for example, just like it is on the manpage. Putting it just like @ next to ? or <asterisk>, implies that it just goes like that alone.
> Overview of Bash Symbols
> $(( )) is used for saving the output of arithmetic.
I guess you could save it, but you can also pass it directly to where you need it. I wouldn't call `echo $(( 1 + 2 ))` saving it.
> $[] deprecated integer expansion construct which is replaced by (( ))
No, it's replaced by `$(())`.
EDIT: Removed the part about the file types. You have that covered. However, you wrote
> c Special file
> b Block device
They're both special files. `c` is for character devices.