(1) Short for
transistor-transistor logic, a common type of digital circuit in which the output is derived from two transistors. The first
semiconductors using TTL were developed by
Texas Instruments in 1965. The term is commonly used to describe any system based on digital circuitry, as in
TTL monitor.
(2) Short for Time to Live, a field in the Internet Protocol (IP) that specifies how many more hops a packet can travel before being discarded or returned.
(3) Short for through-the-lens it is a name
for the LCD screen on a digital camera that shows what is projected onto the
sensor by the lens. This is an alternate to using the optical or electronic
viewfinder. Also called a TTL viewfinder.
