URL

Uniform Resource Locator is the address of a standard Resource on the Internet.

Component: Protocol domain name or IP port number Path query string anchor point

https://www.baidu.com/s?wd=hi&rsv_spt=1#2
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DNS

The Domain Name System is a service of the Internet. As a distributed database that maps domain names and IP addresses to each other, it makes it easier for people to access the Internet.

The nslookup command is used to query DNS records to check whether domain name resolution is normal and diagnose network faults.

➜ ~ nslookup Baidu.com Server: 114.114.114.114 Address: 114.114.114.114#53 Non-authoritative answer: Name: Name: baidu.com Address: 220.181.38.148Copy the code

IP

The Internet Protocol, also known as the Internet Protocol, is a Protocol used for packet-switched data networks.

The ping command is used to test whether data packets can reach a specific host through IP. Return packet loss rate (packet loss rate) and round-trip delay time (network delay, round-trip delay time).

➜ ~ ping baidu.com ping baidu.com (39.156.69.79): 56 data bytes 64 bytes from 39.156.69.79: Icmp_seq =0 TTL =53 time=25.635 ms 64 bytes from 39.156.69.79: Icmp_seq =1 TTL =53 time=37.382 ms 64 bytes from 39.156.69.79: Icmp_seq =2 TTL =53 time=37.884 ms 64 bytes from 39.156.69.79: Icmp_seq =3 TTL =53 time=28.861 ms 64 bytes from 39.156.69.79: ICmp_seq =4 TTL =53 time=25.029 msCopy the code

The domain name

A Domain Name is the Name of a computer or computer group on the Internet, which consists of a series of characters separated by dots.

Domain name level:

For example: www.baidu.com

  • Com top-level domain,
  • Baidu.com Secondary domain name
  • www.baidu.com Level 3 domain name.

Domain name type:

  • COM A commercial organization or company
  • A TOP, benchmark organization or individual
  • 1. Technology
  • ORG A non-profit organization or group
  • GOV Government Department
  • MIL Military division
  • NET An organization or company that works on the Internet
  • EDU Educational Institution