[jggimi]

Thank you for taking the time to read this short introduction to networking. To obtain it:

1. Your browser extracted the www.daemonforums.org domain name from the URL for this page.
2. It requested the IP address for the domain name from your DNS server, using UDP.
3. The UDP packet became a payload of an IP packet.
4. The IP packet became a payload of an Ethernet frame.
5. The Ethernet frame was placed on the LAN with the destination the MAC address of your router, to forward to the DNS server at your ISP.
6. Your router then extracted the IP packet from the Ethernet frame and placed it in a frame for the next link: perhaps another Ethernet network, or a PPP network, or a DSL network. It translated your private network address in the IP packet and source port in the UDP packet as it did so.
7. When the router received the reply, the IP packet was extracted from that network frame and was placed on an Ethernet frame with the destination of your computer's MAC address, after translating the inbound IP address and port accordingly.
8. On arrival at your computer, the IP packet was extracted from the Ethernet frame, the UDP packet from the IP packet, the DNS response from the UDP packet.
9. Your browser initiated a TCP session with the website here, using the IP address just received. This caused a 3-way handshake to establish a TCP session. Your computer sent a TCP packet, the web server replied with a TCP packet, and your computer sent a second TCP packet. Each of these was encapsulated in an IP packet, and then encapsulated in an Ethernet frame as with the UDP DNS request above.
10. Your browser then submitted an HTTP request over the established TCP session. The HTTP request includes identifying information, so that the web server here knows if you are logged in or a guest.
11. The webserver responded with this page, via a series of TCP packets.
12. The TCP session was terminated, with a variable size handshake.

This procedure to submit an HTTP request and receive a web page back is pretty complex, isn't it? Yes. And I've simplified it. There may have been packet fragmentation, packets resent, packets reordered. And of course, there were multiple HTTP requests for graphic images, with repetition of these steps for each request.

After all, this is only a simple introduction. It is not intended to provide answers; instead, its to help you articulate better questions.