CHARMM Development Project Forums User Discussion & Questions Setup, I/O, and Basic questions What does UNIT stand for?

Hi all

In all the scripts you open a UNIT with a number afterwards. What does this UNIT stand for? What does it do? Is certain numbers reserved and what do the numebrs stand for?

Thanks!!!!!

The document, io.doc will be helpful!

I don't seem to find anything on UNIT in either io.doc or usage.doc? Any other files where I may look?

Sorry for incorrect information.
From usage.doc
Fortran I/O Units Usage by CHARMM
In order to keep CHARMM as machine independent as possible, all
specification of files is done through Fortran unit numbers. Two unit
numbers have special signifigance, 5 and 6. Unit 5 is the command file
interpreted by CHARMM. Unit 6 is the output file for all printed
messages. As commands are read from unit 5, they are echoed on unit 6.
All other unit numbers have no predefined meaning. The CHARMM OPEN
command may be used to assign files to units.

It just follows fortran's I/O rules.