The front mast is called the Foremast. Sometimes it is called the mizzen mast.
The most common single masted sailing vessel with a mainsail and one jib is the sloop.A cutter has one mast with one mainsail but two jibs.A catboat has one mast and a huge mainsail but (usually) no jib. The mast is located very much forward on the vessel.There are other sailboats that have just one mast and a mainsail such as the Sunfish or a Dhow, both of which have a lateen rig (one mast, one mainsail.)
yacht this was the original answer but this can refer to a powered vessel too. As in motor yacht. A one masted fore and aft rigged vessel is called a sloop and can have various sail plans e.g. Gaff rigged, bermudian rigged
The lateen sail looks like a triangle. The point is on one side and the base is on the other side. The base of the sail would be parallel to the main mast. A spar at the top of the sail is attached to the mast. It is mainly used on sunfish and other extremely small sailing craft.
Between the mast and the boom. On ships with one mast, itt is located directly between port and starboard, and more towards the bow than the stern.
The powerboat. The vessel that has the greatest ability to get out of the way of the other one has the duty to do that.
Halyards are used on a sailing vessel to haul up sails. One end is connected to the top of the sail (the head) and it is led up to the top of the mast, through a block (pulley) and back down. Pulling down on the halyard pulls the sail up. With larger sails a winch is used to assist. When the sail is up all the way, the halyard is 'made fast' or 'cleated.'
Powerboat. The powerboat is easier to maneuver and turn than a vessel depending on sail and wind.
The most forward sail is normally called a jib.On vessels with more than one jib, the names of the jibs (from forward to aft) are: Flying jib, Outer jib, Inner jib and Fore (topmast) staysail.
a dinghy would be a small (6 to 16 foot) sailboat, these can have almost any sail rig. the type of rig you described is called a sloop. a sloop is a sailboat with a triangular mainsail and a jib (this sail configuration is called a marconi rig, or bermudian rig), and are very common. so a small, one masted vessel with a mainsail and jib would just be called a sloop, or dinghy.
Powerboat. The powerboat is easier to maneuver and turn than a vessel depending on sail and wind.
A power boat cannot stop or turn as fast, especially a vessel larger than the sail boat . The sail boat should give way to the power boat.