What is the primary purpose of cookies in web applications?

What is the primary purpose of cookies in web applications?

• A. Maintain session state
• B. Encrypt all data
• C. Prevent SQL injection
• D. Authenticate users automatically

Answer: (A)

Cookies are used to keep track of a user's session across the stateless HTTP requests. Since each request is independent, the server wouldn’t know who you are or what you were doing on a previous page without a way to link requests. A cookie stores a session identifier on the client, and that identifier lets the server retrieve the user’s session data on subsequent requests—so things like being logged in, items in a shopping cart, or user preferences persist as you navigate the site. This continuity is the main reason cookies exist in web apps. Encryption of all data isn’t handled by cookies themselves; data in transit is protected by TLS, and sensitive data should be protected by proper server-side storage and secure design. Preventing SQL injection relies on input validation and parameterized queries, not cookies. Automatic user authentication isn’t performed by cookies; authentication is the process that verifies credentials and, after success, often issues a session (which the cookie may carry as a token). So the best answer is that cookies primarily maintain session state across requests.

Cookies are used to keep track of a user's session across the stateless HTTP requests. Since each request is independent, the server wouldn’t know who you are or what you were doing on a previous page without a way to link requests. A cookie stores a session identifier on the client, and that identifier lets the server retrieve the user’s session data on subsequent requests—so things like being logged in, items in a shopping cart, or user preferences persist as you navigate the site. This continuity is the main reason cookies exist in web apps.

Encryption of all data isn’t handled by cookies themselves; data in transit is protected by TLS, and sensitive data should be protected by proper server-side storage and secure design. Preventing SQL injection relies on input validation and parameterized queries, not cookies. Automatic user authentication isn’t performed by cookies; authentication is the process that verifies credentials and, after success, often issues a session (which the cookie may carry as a token). So the best answer is that cookies primarily maintain session state across requests.