Masts, or see: http://wiki.answers.com/Q/What_are_ship_poles_calledfor a more indepth answer.
Yes, but there are many bridges, so it is easier to remove your masts and motor along on your trip.
Most are classified by length. Larger racing ones by 'tonnage'. There are also special classifications by number of masts etc.
A brig
It is a Ketch
They are basically a 'relay station' The handset transmits a signal to the nearest masts, and the masts re-transmit the signal to the next mast, and the next etc... until the call reaches its destination.
"Helmsman".
A schooner may have 2 or more masts.A ketch has two masts, with wheelhouse between them, longitudinally speaking.A yawl has two masts, with wheelhouse abaft of both.A brigantine has two masts.There are others, we are not alone!
Portable (cell) phones are low-power devices - they have a limited range. Each mobile-phone communicates with at least three mobile 'masts' to establish its location so the network can keep the call connected. These masts cover a set area - or 'cell' (which is why americans call them cell-phones). The masts communicate with each other to connect the call to its destination.
masts are sails on yachts.
A barque has 3 (or sometimes more) masts.
Turtle, that is what you call it when you tip your sailboat upside down