What is header in TCP protocol?

Related questions

1. Is TCP or UDP better?
2. What is DSCP in IP header?
3. How does TCP header work?
4. How long is TCP header?
5. How many bytes is a TCP header?
6. How is UDP checksum calculated?
7. What is the maximum port number?
8. Is port 443 encrypted?
9. What TCP header contains?
10. Where is UDP used?

Tags

1. #connection
2. #protocol
3. #control
4. #everything
5. #reliable
6. #acknowledged
7. #receiver
8. #transport
9. #header
10. #before
11. #transmission
12. #sending
13. #sends
14. #establishes