What is data encryption primarily used for in terms of data at rest?

Data encryption is primarily used to protect data from unauthorized access, particularly when the data is stored, which is referred to as "data at rest." When data is encrypted, it is transformed into an unreadable format using cryptographic algorithms. Only authorized users with the correct decryption key can access the original data. This is crucial for safeguarding sensitive information, such as personal data, financial records, and proprietary business information, from potential threats like data breaches or unauthorized intrusions.

The other potential uses, such as improving data transmission speed, ensuring data integrity, or facilitating data analysis, do not align with the primary function of encryption. While integrity checks can occur in the context of encrypted data, they are not the main purpose of encryption itself. Similarly, encryption does not inherently make data analysis easier; instead, it often requires additional steps to decrypt data before analysis can occur. Thus, protecting data from unauthorized access stands out as the correct focus for encryption at rest.