The offer is the fruit of pre-contractual negotiations, but it does not end the precontractual stage, because it does not alone lead to the conclusion of the contract, but rather a corresponding acceptance must coincide with it. An affirmation was addressed to him, i.e., it agrees with the offer in all the issues it addressed, it is equal in that these issues are essential or secondary, every issue mentioned in the offer must be dealt with by acceptance, regardless of its importance.And if the contract is concluded by the connection of acceptance with the knowledge of the obligor, the question arises whether it is sufficient for the contract to converge acceptance and offer on the essential issues, or should this extend to all the detailed issues, so does the agreement on the essential issues lead to the completion of the contract? Or is this considered a stage of the negotiations that did not take place after the contract, and the contract is not concluded until after the agreement is extended to secondary issues as well? By collecting jurisprudence, it is not necessary for the conclusion of the contract that all issues be agreed upon as a matter, but rather that it is sufficient to agree on the essential issues for the conclusion of the contract