Basic Web Concepts

First, the basic concept of the Web

• Static code and dynamic code

Static code is the code written in Html,css,javascript, dynamic code is the use of Web scripting language, such as PHP, ASP, ASP. NET, JSP and other code written

• Static and Dynamic Web sites

1. The biggest difference between static and dynamic Web pages is that the Web page is fixed content or can be updated online.

2. Static Web page refers to the non-application and directly or indirectly produced HTML pages, the content of such a Web page is fixed, modification and update must be through dedicated web authoring tools, such as Dreamweaver, FrontPage, etc. And as long as you modify a character in the Web page or a picture to be re-uploaded once overwrite the original page. Each static Web page has a fixed URL, the filenames are in the HTM, HTML, shtml, and so on as the suffix; when a static web page is posted to the server, whether or not it is accessed, it is a standalone file; the content of static Web pages is relatively stable and does not contain special code, so it is easy to be searched by search engines. HTML is more suitable for SEO search engine optimization. Static web site does not support the database, in the production and maintenance of the site is large; because it does not need to work through the database, static Web page access speed is relatively fast; now the popular CMS support static Web page, which is helpful to be indexed by search engines and improve access speed, but need to occupy a larger server space, The program consumes server resources when generating HTML, and it is recommended that such operations be performed when the server is idle.

3. Dynamic Web page refers to the use of Web scripting language, such as PHP, ASP, ASP, JSP, etc., through the script to store the content of the site dynamically to the database, the user access to the Web site is to read the database to dynamically generate Web pages method. The site is mainly based on some framework, the content of the Web page is mostly stored in the database.

Dynamic Web site can realize interactive functions, such as user registration, information publishing, product display, order management, and so on; Dynamic web pages do not exist independently of the server's Web page file, but the browser makes a request to the Web page, the Dynamic Web page contains server-side script, so the page file name is often used in ASP, JSP, PHP and so on as a suffix. However, you can also use URL-static technology to make the page suffix appear as HTML. Therefore, the page file suffix can not be used to judge the site's dynamic and static unique criteria. Dynamic Web pages because of the need for database processing, so the dynamic site access speed greatly slowed down; Dynamic web pages because of the existence of special code, so compared to static Web pages, the search engine is relatively less friendly. However, with the improvement of computer performance and the increase of network bandwidth, the last two articles have been basically solved.

• Internet

Internet (English: Internet), also known as a network, or transliteration of the Internet (Internet), the Internet, the Web began in 1969, the United States of Apache network. is a vast network of networks and networks, which are interconnected by a common set of protocols and form a single, large, logical international network. Usually the Internet refers to the Internet, while the Internet refers to the Internet. This method of connecting computer networks to each other can be called "Network Interconnection", on the basis of which a global Internet network called the Internet, which is connected with each other, is developed. The internet is not the same as the World Wide Web, which is a global system based on hypertext links and one of the services that the Internet can provide. (Baidu Encyclopedia)

• Web server

Web servers generally refer to Web servers, which are programs that reside on some type of computer on the Internet, can provide documents to Web clients such as browsers, or they can place Web site files for worldwide browsing; You can place data files for download worldwide. Currently the most mainstream three Web servers are Apache Nginx IIS.

• IP Address

IP address refers to the Internet Protocol address (English: Internet Protocol address, and also translated as Internet Protocol addresses), is the abbreviation of IP address. IP address is a unified address format provided by the IP protocol, which allocates a logical address for each network on the Internet and each host to block differences in physical addresses. There are still some IP agent software, but most of them are charged.

• Domain name

Domain name, or domain name, is the name of a computer or group of computers on the Internet consisting of a dotted list of names used to identify the computer's electronic orientation (and sometimes geographic location) when data is transferred.

The Domain Name System (dns,domain name systems, sometimes referred to as domain names) is a core service of the Internet, as a distributed database that can map domain names and IP addresses to each other, making it easier for people to access the Internet. Instead of remembering the number of IP addresses that can be read directly by the machine.

• DNS Server

DNS (domain name server, nameservers) is the server that is transforming the domain name and the corresponding IP address. DNS holds a domain name and the corresponding IP address (IP addresses) table to resolve the domain name of the message. A domain is the name of a computer or group of computers on the Internet that identifies the computer's electronic orientation (and sometimes geographic location) when data is transferred. A domain name consists of a string of dotted names, usually containing an organization name, and always includes a two to three letter suffix to indicate the type of organization or the country or region in which the domain resides. DNS is the abbreviation for a computer domain Name System or domain name Service, which consists of a domain name resolver and a domain name server. A domain name server is a domain name and corresponding IP address that holds all the hosts in the network, and a server that converts the domain name to the IP address feature. Where the domain name must correspond to an IP address, an IP address can have more than one domain name, and the IP address does not necessarily have a domain name. The domain Name system uses a hierarchical structure similar to the directory tree. A domain name server is typically a server side in client/server mode, and it has two main forms: the primary and the forward server. The process of mapping a domain name to an IP address is called "Domain name resolution."

• Host File

Hosts is a system file without extension, can be opened with Notepad and other tools, its role is to use some of the common URL domain name and its corresponding IP address to establish an association "database", when the user in the browser to enter a need to log in the URL, The system will automatically find the corresponding IP address from the Hosts file, once found, the system will immediately open the corresponding Web page, if not found, the system will submit the URL to the DNS domain name resolution server for IP address resolution. It is important to note that the mappings for the Hosts file configuration are static and will not be accessible if the computer on the network has changed to update the IP address in a timely manner.

Basic Web Concepts