[O] Summary of syntax?

[Alan Schmitt]

Hello,

I was just reading a document in org mode that had some code written 
like this:

: make
: make install

I wanted to know more about this syntax (colon at the start of the 
line), so I went to the manual and searched for it. Unfortunately I 
could not find it, nor could I find a summary of the syntax for org 
files.

Is there a syntax reference card somewhere?

Thanks a lot,

Alan