I'm quite late, but I thought I'd add my input: if your goal is to have some command like
htmldocs some/path/or/file
you can write your own script inside a personal scripts folder, e.g., /usr/utils, add that folder to your PATH (in your .bashrc file - see What is the .bashrc file?), and then just execute your personal command.
This way, I've been able to define my own scripts that do whatever I want, e.g.,
sprocs
my own command which runs
ps -ef | grep Server
so I can easily see what server processes are running on my machine.
An example of a script's contents would be like
#!/bin/bash
ps -ef | grep Server
echo "my message to output in terminal"
# etc...
and this file, call it 'sprocs' (no extension) or something, would be in the folder you made / any folder that is on your PATH, so you can just type 'sprocs' in your terminal, and it just works.
https://www.linux.com/learn/tutorials/284789-writing-a-simple-bash-script- describes how to get started with your own script. The #!/bin/bash is the standard first line that just lets your terminal access the commands. If you used python, it would be #!/usr/bin/python (assuming that's where python is installed).
Your case might have different commands like
#!/bin/bash
cd /usr/share/doc/ecb/html
firefox somefile.html
# etc...
If you wanted flexibility, you probably want to pass parameters, so you could check out http://floppix.ccai.com/scripts1.html for an example at the bottom.
(Even if you don't do this, it's definitely useful for running personal scripts from terminal that do exactly what you want.)