Tutorial: Lesson 1
FDO stands for Form Definition Order.
FDO is the programming language in which AOL communicates.
This site focuces on the 1991 version of FDO, appropriately
called FDO91 which is still used today.
Want to see what FDO streams look like? By the way, an FDO
stream is a set of FDO coding. To do this the Star
Tool needs to be installed on your computer. The Star
Tool, also know as Master AOL, is a tool used by AOL developers
to test features still being made. We will utilize its FDO
- Once the Star Tool is installed, click the "*" menu and
go to "Atomic Debugger". This program allows you
to view the FDO streams being sent and received by the AOL
client. America Online 5.0's Atomic Debugger is pictured
- Click Setup Options > Setup (Ctrl + Enter).
- To turn the Atomic Debugger on, check the box entitled
"Atom Trace" in the "Settings" window. The Atomic Debugger
will now be on.
- Close the "Settings" windows and minimize the Atomic Debugger.
- Next, go in AOL and click around, enter a chat room, open
your Buddy List, do anything that brings up new windows.
Now go back to the Atomic Debugger.
- Before looking at the code go back to the "Settings" window
and uncheck the "Atom Trace" box.
- Now you can go and look at the code. Do not be overwhelmed
by the surfeit of code.
If you still want to learn more, procede on.
The areas below in red are atoms.
sm_m_send_token_arg <"f1", 32-30>
AOL-Files.com is working to compile a full database with
the function of every atom (there are over 1800). FDO
tutorials are unheard of. I have heard rumors that very few
people at AOL have the FDO91 Manual. I will pay money for
any professionally written, extensive, and full tutorial.
Name your price.
AOL also communicates using tokens. Tokens have two
parts. First, is a two character category which is also called
a token. Second, is an argument which can be one of the three
- Value: The argument is a number. A detailed explanation
of values can be found at BMB's Arguments
Tutorial. These are usually used to open new windows.
- String: The argument is a string. For those that
don't know, a string can be considered the same as what
we call sentences. These are used when the user sets the
string to be sent.
- Raw: Nothing is sent with the token. Ususally opens
Every window fits into a catagory. For example, most windows
that you are probably accostumed to seeing are f1 tokens.
These are also know as invokes. These are also easiest for
you to access. To get to f1 tokens you need to have the Star
Tool installed on AOL. Once you have that installed click
the Star Menu, "*", then go to Database... > Invoke Database
Record. It looks as follows.