What's the whole point of "localhost", hosts and ports at all?
I'm totally new to this web development stuff. So I see things like "localhost" all the time and ask myself: What's that?
I feel to know what a "host" actually is. Something that executes something. So my mac is the host for everything that runs on it. So "localhost" is actually just my mac? Can I have also other hosts? like "otherhost" or "betterhost"?
So when I write in my browser: http://localhost:80/mysite/index.php, this "localhost" thing tells the browser to look on my machine for that stuff rather than online?
Maybe someone can clear this up a little bit :-)
Solution 1:
In computer networking, localhost (meaning "this computer") is the standard hostname given to the address of the loopback network interface.
Localhost always translates to the loopback IP address 127.0.0.1 in IPv4.
It is also used instead of the hostname of a computer. For example, directing a web browser installed on a system running an HTTP server to http://localhost will display the home page of the local web site.
Source: Wikipedia - Localhost.
The :80 part is the TCP port. You can consider these ports as communications endpoints on a particular IP address (in the case of localhost - 127.0.0.1). The IANA is responsible for maintaining the official assignments of standard port numbers for specific services. Port 80 happens to be the standard port for HTTP.
Solution 2:
" In computer networking, a network host, Internet host, host, or Internet node is a computer connected to the Internet - or more generically - to any type of data network. A network host can host information resources as well as application software for providing network services. "-Wikipedia
Local host is a special name given to the local machine or that you are working on, ussually its IP Address is 127.0.0.1. However you can define it to be anything.
There are multiple Network services running on each host for example Apache/IIS( Http Web Server),Mail Clients, FTP clients etc. Each service has a specific port associated with it. You can think of it as this.
In every home, there is one mailbox and multiple people. The mailbox is a host. Your own home mailbox is a localhost. Each person in a home has a room. All letters for that person are sent to his room, hence the room number is a port.
Solution 3:
Port: In simple language, "Port" is a number used by a particular software to identify its data coming from internet.
Each software, like Skype, Chrome, Youtube has its own port number and that's how they know which internet data is for itself.
Socket: "IP address and Port " together is called "Socket". It is used by another computer to send data to one particular computer's particular software.
IP address is used to identify the computer and Port is to identify the software such as IE, Chrome, Skype etc.
In every home, there is one mailbox and multiple people. The mailbox is a host. Your own home mailbox is a localhost. Each person in a home has a room. All letters for that person are sent to his room, hence the room number is a port.