This tab shows the headers that were sent to and received from the web server. The size of the two lists can be adjusted by dragging the vertical line that separates them.
The left hand list shows the headers that were sent in the HTTP request. The entry named (Request-Line) is the first line of the HTTP request and contains the HTTP method, HTTP version and URL sub path, e.g.
GET /library/index.htm HTTP/1.1
The right hand list shows the headers that were received in the HTTP response. The entry named (Status-Line) is the first line of the HTTP response and contains the HTTP status code, version and description, e.g.
HTTP/1.1 200 OK