Trireme was a warship, that many times people used it as cargo ship as well. It was a very weightless ship.
The ingenuity of this ship was that it gathered more oarsmen, in contradiction with the other ships of that period, having as a result to increase its propulsive strength, without proportionally having to increase its length.
The Athenian trireme was a galley of about 38 meters in length, a beam of 6 meters, a depth of 3 meter, and a draft of 1 meter...They could row the galley at speeds of about 7 knots (13 km/h). The main weapon of the galley was the ram, an extension forward of the keel designed to penetrate enemy ships. A small number of soldiers were also carried.
Sea battles were very common before the 5th century. The trireme was used to ram into enemy ship and render it unstable without losing its own stability. The soldiers would then board the enemy ship and fight like soldiers do on land.
The Greeks had the strongest and the most skillful fleet of ships in their era. One particular Peloponnesian commander in the name of Phormio sailed right into enemy ships and encircled them with his own fleet. This happened at the battle of Naupactus, when ultimately Phormio attacked and defeated the enemy.
Triremes were very unstable when there were storms in the Mediterranean. Drowning of crew members was very common. When the trireme rammed the enemy ship, the rowers in the base had a terrible time full of havoc. Many of them either died in the wreckage or were held prisoners by the enemy.
According to the Ancient Greek historian, Thucydides, it was the Corinthians who first developed the trireme, possibly as early as the 7th century BC. (1.12.4 - 13.2) They in turn based their design on ships first made by the Phoenicians, a people living on the coast of what is now Lebanon.
(At the Battle of Salamis) The narrow channel provided the perfect place for an ambush. Persian ship after Persian ship sailed into the channel only to be annilated by a Greek trireme. As previously mentioned, the trireme has superior manueverability which gave it a major advantage in the narrow waters.
Greek ships had sails, and were pushed along by the wind. Small trading ships usually stayed close to the shore, so the sailors did not get lost. Before a voyage, the sailors prayed to the sea god Poseidon, for a safe journey.
Greek warships had oars as well as sails. The largest warships had three banks of oars and were called triremes. A trireme needed 170 men to row it - one man to each oar. It had a long narrow deck that soldiers could run along and fight from. The oarsmen sat underneath the deck.
Triremes derived their name from having three banks of rowers, who sat almost on top of each other on each side of the ship. Built for speed and maneuverability rather than strength, they relied primarily on the muscle-power of their 170 rowers and used their front ram to devastating effect, especially in such battles as Salamis in 480 BC...Maintaining triremes was expensive, and richer aristocrats would usually pay the costs for one or more ships as both a form of tax and a way of increasing their prestige in the political arena.
With thousands of kilometers of coastline and hundreds of islands, the Greek world was likely to be dominated only by a naval power. A generation after the establishment of democracy Athens became such a power under the influence of Themistokles.
The introduction of the trireme into Greek navies was an event of great political importance, which may fairly be compared to the introduction of the ‘all-big-gun’ battleship into the British Navy in 1907. Heavier, more powerful, and capable of carrying more, but making greater demands on timber supplies and manpower, the trireme not only rendered obsolete all existing Greek line-of-battle ships but gave a decisive advantage to those States whose resources in materials and men enabled them to create and maintain adequate fleets of the new type of warship.