Online signing means that in the real estate field, online signing means that after both parties sign a contract, they go to the relevant real estate department to register it and publish it online. Then an online visa number will be given, and users can check online through the online visa number. Online signing is to make real estate transactions more transparent and prevent "one house from selling more than one house". The contract can be revoked after it is signed. The general "online signing" procedure is: 1. The parties to the transaction negotiate and draft relevant terms based on the commercial housing deposit agreement or sales contract text published online; 2. The real estate development enterprise prints the agreement or contract confirmed by both parties through the online signing system; 3. Signature (seal) of both parties; 4. Indicate on the electronic property list that the commercial house has been reserved or signed. In the field of e-commerce, it can also be called electronic contract signing and online contract signing. In order to prevent intermediaries from unilaterally "signing online" without authorization, the Municipal Housing and Urban-Rural Development Commission issued the "Notice on Improving the Online Signing Process of Existing House Sales Contracts and Other Relevant Issues" stipulates that if both parties to the transaction do not sign or seal the contract, the real estate agency will sign online without authorization. If the information is submitted, after verification, the online contracting behavior of the organization or personnel will be restricted, and the violations will be publicly exposed. In serious cases, the violations will be recorded in the credit files of the organization or personnel.