1. Daily data: refers to daily business data, including sales records and inventory information. These data are very important for daily operation and decision-making, because they reflect the company's operating conditions and trends.

2. Sensitive data: This kind of data has certain sensitivity or privacy, such as customer personal information and payment information. This kind of data needs strict access control and protection to prevent data leakage and abuse.

3. Confidential data: This is the most confidential and important data, such as business plans and strategic information. This kind of data can usually only be accessed and processed by authorized personnel to ensure that the company's core interests and competitive advantages are not damaged. In order to ensure the security of data, Wal-Mart may take various security measures, including data encryption, access control, periodic audit, etc. At the same time, the company may also carry out relevant data protection training for employees to improve their awareness of data protection.