In the context of mandatory law, a contract of sale is a consensual, bilateral, chargeable and reciprocal contract. It is also an informal contract, except when the subject matter is the purchase of real estate and when it is a hire purchase, because then the purchase contract must be formal, i.e. it must be in writing. The parties to this contract are the buyer and the seller, both of then must be natural or legal persons. The object of the merchandise is usually movable or immovable property, but may also be rights in rem of credit. The main objective that the parties to this contract want to achieve is the transfer of ownership of a certain thing in exchange for a appropriate monetary equivalent. The Code of Obligations constitutes a fundamental source of law and a general legal framework governing matters relating to the sale of goods. In the case of online purchases, when the contracting parties conclude a distance sales contract, the laws governing electronic commerce and consumer protection apply in addition to the aforementioned basic source of law. In the Republic of Croatia, the lay governing the sale of goods and services is based on the lay of the Republic of Croatia, which provides that the sale of goods and services is subject to the law of the Republic of Croatia. After an initial theoretical analysis of the contract in question and its types, this paper places particular emphasis an the rights and obligations of the contracting parties arising from the conclusion of a contract of sale by electronic means, i.e. in electronic form. The contracting authority shall inform the buyer of the name of the contracting entity and of the name of the contracting entity.