What is the internet?
A large network of interconnected computers throughout the world. In turn, this large network is made up of smaller groups of networks that can be local (LAN) or larger (WAN).
The Internet can be considered as a huge repository of general and specialized information, in the form of texts, images, sound documents, videos, etc.
How does it work?
Communication on the Internet is established between two points: one is the personal computer from which the internet is accessed, and another is any of the servers that are on the network and that provide the information.
Each computer that participates on the internet is called a node or host . Some nodes serve the information by what are called servers . Other computers, such as the one you are using, request and consume the information, and are called a client .
Communication between nodes on the internet is done through a series of rules and protocols called TCP / IP that regulate said communication.
Each host on the internet is identified by a unique IP address. Each IP address is formed by a group of 4 bytes (4 numbers between 0-255 separated by periods).
An example of an IP address is 192.168.14.2
Associated with the IP Address is the Mask . It also has a form and values within the possible IP Address, and its purpose is to narrow the range of other IP addresses with which we can communicate directly, that is, they are on the same network. Thus an IP Address and its Mask delimit a network.
Example:
A computer with the following configuration can only communicate with computers that start with 192.168, that is, that belong to the 192.168.0.0 network
- IP Address: 192.168.2.14
- Mask: 255.255.0.0
If the computer wishes to communicate with other computers, which do not belong to the 192.168.0.0 network, it must use a gateway or gateway.
What is a gateway or gateway?
The gateway is a device connected to at least 2 networks and allows communication between them. Usually these are specific devices called routers. Although it can be a computer with several network cards, such as the lliurex classroom server that connects to 2 networks, and acts as a gateway for computers in the computer room.
What is a DNS?
Remembering cryptic IP addresses is difficult, so a domain name server (DNS) is usually used, which translates domain names into IP addresses. Domain names are the usual way to name hosts on the internet.
When necessary, convert the domain name such as www.google.com to IP address 74.125.39.104 .
You can verify with a browser that we get the same by typing http://www.google.com that http://74.125.39.104 which is the IP address.
How is an internet address signed?
All websites have a specific location on the Internet. It is this address that is used to reach them. The technical name is URL (Uniform Resource Locator) or a uniform resource locator.
The structure of an internet address such as www.hrfaysal.com is as follows:
- http: // indicates to the browser that you must connect to a web-type site, using in the protocol communication or set of rules http ( H yper T ext T ransfer P rotocol)
- www indicates the name of the server
- gva indicates that the machine is in the domain of the Valencian Generalitat
- It is indicates that the site is located in Spain. The most frequent names are
- com commercial sites
- edu educational institutions
- net organizations or companies related to telecommunications
- org non-governmental organizations
- us, uk, es, fr, … countries
How do I locate the information on the internet?
One of the most frequent uses of the Internet is information consultation. The number of pages with information of all kinds and in all languages is incalculable. But this huge amount of available information is not organized.
One of the most surprising things on the Internet is how easy and fast it is to search, and the things we can find. To help us in that search we have what are called search engines. For example, Google, http://www.google.com/ .