FAX is an abbreviation of facsimile, which comes from Latin 'fac simile' meaning "make similar". It is a telecommunication technology used to transfer copies (facsimiles) of documents, especially using affordable devices operating over the telephone network.
Fax is a system used for tranmission of text messages. This fax system uses the normal fixed telephone network on shore, connecting all telephones. It's even possible to send faxes to Inmarsat terminals with telephone capability such as Inmarsat B, M or F77.
When you send a fax via the Inmarsat C terminal you have to compose a text message in the ASCII protocol. When you are going to transmit the message you have to mark it in the transmit menu (address book) as a fax.

Practise on the Inmarsat C simulator

For preparing and sending a fax:

• Select 'File' in the Menubar on the top of the screen by using the arrow keys followed by 'Enter'.
• Select 'New ASCII' by using the arrow keys followed by 'Enter'.
• Now the cursor is blinking on the top of the Text field and the text can be added by typing it in using the keyboard.
• When the text has been entered you can transmit it immediately (Alt,T combination to enter the transmit menu) or save it (Alt,F,S combination to enter the file save menu).
• Go to the address book by touching the spacebar.
• Select a fax address using the arrow keys and press 'Enter' or add a new one to the address book.
  
• Go to the Land Station using the arrow buttons and touch the 'Space Bar' and then select a Land Earth Station using the arrow keys and confirm your choice by pressing 'Enter'
• Go to '[X] Text in editor ' using the arrow keys (by-pass this item when you wish to send your text message from the screen): touching the 'space bar' in this position will remove the mark showing '[ ] Text in editor ' and 'File:' below this field this option can be used to transmit a saved file.
  
• Go to the priority menu by using the arrow keys and select priority of message (Routine or Non Urgent) by using the 'space bar'.
  
• Go to the request confirmation by using the arrow keys and decide if you wish to have a delivery confimation request, which can be selected by using the 'space bar'
• Go to Print by using the arrow keys and decide if you want to print the file, which can be selected by using the 'space bar'.
• Go to immediate transmission by using the arrow keys and decide if you want a direct transmission, this can be selected by using the 'space bar'.
• Go to Send using the arrow keys and press 'enter' (or enter password if protected).
• The Fax will now be transmitted to the LES and after successful delivery you will get a confirmation, if you've chosen this option.
• During the transmission of the message the indication light 'Send' on the transceiver is blinking and the status field on the screen shows 'Sending'.

The process of delivery of messages can be monitored in the 'transmit log'.