Types of Modem

There are three types of modems.

DIRECT CONNECT: 
Which are linked to the computer by cable and the Rs.232 point and plus in to a standard telephone socket.
INTERNAL: 
Which are built in to the computer and have backup capabilities.
Sales of micro-computers which contain internal, board-mounted modems are increasing rapidly. Alternatively, there are add-on modem cards that can be fitted inside the computer.
ACOUSTIC COUPLER: 
A cheap, low-speed modem where the user places the telephone handset in to the cradle of the coupler.