they traded mostly food.
They traded items that the have a surplus of for items that they cannot get.
Greeks
they traded pizza and bread
they used big boats
With thier colonies and other peoples and cities around the Mediterranean and Black Seas.
They used the sea.
In pursuit of knowledge, trade and financial advantage.
Through agriculture, mining and trade.
they had a connection to the Aegean sea
because they were poor and about to go out of food
The Greeks had great trade routes with the rivers nearby. They also had plenty of supplies to trade. With that they would hope to earn something greater.
Trade was very important to the Ancient Greeks because the only real thing that could bring money into Ancient Greece would be olives and olive oil (and sometimes wool) but without trade there would be no income as you could trade 20 pints of olive oil for three cows and that's how the world worked back then.