I used firefox extension LIVE HTTP HEADERS while browsing a website and got these headers

Code:
http://website21.fc2.com/up/wNLzTu.flv?m=e783f126fa3bab129c8e0bdb35cae218

GET /up/wNLzTu.flv?m=e783f126fa3bab129c8e0bdb35cae218 HTTP/1.1
Host: website21.fc2.com
User-Agent: Mozilla/5.0 (Windows NT 5.1; rv:19.0) Gecko/20100101 Firefox/19.0
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
Accept-Language: en-US,en;q=0.5
Accept-Encoding: gzip, deflate
Referer: http://video.fc2.com/flv3.swf?t=201303111432
Cookie: PHPSESSID=e95fb0989cf7db81f0b48baf2a75fd4d
Connection: keep-alive

HTTP/1.1 200 OK
Server: nginx/1.2.4
Date: Sat, 16 Mar 2013 06:35:14 GMT
Content-Type: video/x-flv
Content-Length: 49977589
Last-Modified: Sat, 16 Mar 2013 06:26:40 GMT
Connection: keep-alive
Accept-Ranges: bytes
Anyone can please explain me these headers?

Does it means when this URL below is open then these HEADERS were set to open this URL?
Code:
http://website21.fc2.com/up/wNLzTu.flv?m=e783f126fa3bab129c8e0bdb35cae218
When i open this URL on the firefox then i get it working. ( Does it work because all headers / cookies were set to firefox already? ) i want to know what is working behind it

But When i simply copy and paste this URL in other browser then i get 403 FORBIDDEN ( does it mean all headers / cookies were not set to other browser? )


Actually i need to run this URL into my PHP Script, So i think i will have to set these headers into my php script before calling this URL otherwise it will show 403 FORBIDDEN.

Code:
http://website21.fc2.com/up/wNLzTu.flv?m=e783f126fa3bab129c8e0bdb35cae218
Anyone please help