To give something for buying something

Direct exchange of goods against goods without use of money is known as barter system
Barter is a system of exchange where goods or services are directly exchanged for other goods or services without using a medium of exchange, such as money.

this system was followed at the time of civilisation. in this people used to exchange goods for acquiring new goods. for eg now we give money and purchase our required goods. but earlier people used to give their goods to say sellers for acquiring new goods. Also for eg. like if a farmer had wheat aand wants to buy a pair of shoes, then he used o give his wheat to the seller and buy the pair of shoes.(instead of paying him a certain amount of money)

Exchange of goods without money
Exchange of goods without the use of money