I started to answer each question, but its easier to give you just a general statement:
SSB is a subset of frequencies and a protocol for voice communication which can be used for transmitting and receiving voice over distances.
VHF radios that are on boats are line of sight only. Long distance cruisers use SSB primarily to talk to each other, but it is not a required piece of
equipment and not everyone has this aboard. You can use SSB to send and receive
email through paid services such as sailmail, as well as ship to shore
phone services. You don not need to pass a test to perform SSB communication but you do need to pay for a
license.
HAM radio allows you to take advantage of other frequencies and protocols beyond just SSB designated frequencies. However, you need a pass a test to get a
license. Since HAM is an amateur designation, you also cannot perform "business" on HAM designated bands. Like SSB you can also use it to access
email, ship to shore and the like, but you can also connect to users worldwide on other frequencies. There are also a number of other protocols and communication standards that you can utilize; and you can link into a number of HAM nets throughout the world to communicate to multiple users - sort of like conference calls.
Most modern SSB radios are equipped to take advantage of the additional HAM frequencies, but you do need a HAM license to transmit.
Weather fax is not a two way
transmission, and you can actually download
images with any
cheap all band radio receiver, appropriate
software, and a
laptop. You don't need SSB or HAM to do so.
I'd like this thread not to drift into other subjects. The objective in my starting this thread was to get an idea of what mode of operation, protocols (primarily data), bands etc within amateur radio are useful for sailing. For example, the directional needs of leveraging
satellite may not be conductive to using
satellite ham radio on a
boat - as fore-mentioned above.
For another read on communication options, and probably a more appropriate place to expand questions like this - please read this thread
http://www.cruisersforum.com/forums/...ium-43509.html