TechSmart

         Hello guys in this post we are learn about Web servers and different types of Web servers so read carefully  

Web server :-

•  Web Server is a computer where store the all content. Web server is mostly used to host the web sites but there exists other web servers used for storage, FTP(File Transfer Protocol), email etc.
• Website is collection of web pages while web server is software that responds to the request for web resources.

The basic process

• Servers install software like Apache, IIS and hence called Web server which handles primarily Hypertext Transfer Protocol requests through Universal Resource Locator address requests.
• URLs are simply the name of a website that users enter into Web browsers in order to locate a Web page.
• When the user enters a URL, the browser sends an HTTP request to the server computer running Apache, usually on port 80.
• The HTTP protocol is the Internet standard data transfer protocol for Web pages, so when a user makes a URL request to an Apache server, the Apache server will handle the HTTP request and return the requested Web pages.

1.  Apache web server

• The Internet exists as a collection of Web servers that host Web pages that users can access from their computers.
• These servers must run server software to handle user requests.

• An Apache server will handle numerous HTTP requests at a simple time. In order to do this, the server has to run on multiple "threads"  execution.
• A thread is a part of a program that branches off from the main program and runs at the same time in order to accomplish a specific task.
• The Apache server was create a new thread for each HTTP requests that will handle fetching and returning the requested Web page. Apache server serve multiple Web pages at same time to thee user.

• Along this web, the Apache server can allow users to download files to their computers, which Apache will also handle via HTTP.
• These program file server include audio files, movie files and certain documents such as Word documents or PDFs. If the user requests a program file for a scripting language, such as PHP, Python or Perl, then the Apache server executes the program  and sends the output of the program to the user through  HTTP.

2. Internet Information Server (IIS)

• IIS (Internet Information Server) is a group of Internet servers ( including Web or Hypertext Transfer Protocol server and a File Transfer Protocol server) with additional capabilities for Microsoft's windows NT and windows 2000 Server operating system.
• IIS is Microsoft's entry to compete in the Internet server market that in also addressed by Apache, Sun Micro-systems and others.
• With use of  IIS, Microsoft includes a set of programs to building and administering Web sites, a search engine, and support for writing Web- based applications that access database.
• A typical.company that buys IIS can create pages for Web sites using Microsoft Frontpage product (with its WYSIWYG (What You See Is What You Get) user interface).
• Web developers can use Microsoft Active Server Page (ASP) technology, which means that applications including ActiveX controls - can be embedded in Web pages that modify the content sent back to users,
• Microsoft includes special capabilities for server administration designed to appeal to Internet service providers (ISPs). 

3. Proxy server

• A proxy server is a dedicated computer or a software system running on a computer that acts as an intermediary between an endpoint device, such as a computer, and another server from which a user or client is requesting a service. The proxy server may exist in the same machine as a firewall server or it may be on a separate server, which forward requests through the Firewall
• Cache can serve all users this is an advantage of proxy server. If one or more Internet sites are frequently requested, these are likely to be in the proxy cache, which will improve user response time. A proxy can also log its interactions, which can be helpful for troubleshooting

• When a proxy server receives a request for an Internet resource (such as a Web page), it looks in its local cache of previously pages. If it finds the page, it return it to the user without needing to forward the request to the Internet.
• If the page is not in the cache, the proxy server, acting as a client on behalf of the user, uses one of its own IP addresses to request the page from the server out on the Internet. When the page is returned, the proxy server relate it to the original request and forward it on to the user.
• Proxy servers are used for both legal and illegal purposes. In the enterprise, a proxy server is used to facilitate security, administrative control or caching services, among other purposes.
• In a personal computing context, proxy servers are used to enable user privacy and anonymous surfing. Proxy servers can also be used for the opposite purpose: To monitor traffic and undermine user privacy.
• To the user, the proxy server is invisible; all Internet requests and returned responses appear to be directly with the addressed Internet server. The proxy is not actually invisible; its IP address has to be specified as configuration option to the browser or other protocol program.)

4. HTTP Protocol

• HTTP is short for Hyper Text Transfer Protocol. HTTP is the underlying protocol used by the World Wide Web
• Web and this protocol defines how mesons are formatted and transmitted, and what actions web servers and browsers should take in response to various commands
• For example, when you enter a URL in your browser, this actually sends an HTTP command to the Web server directing it to fetch and transmit the requested web page.
• The other main standard that controls how the World Wide Web works is HTML, which covers how Web pages are formatted and displayed.

• HTTP is called a stateless protocol because each command is executed independently, without any knowledge of the commands that came before it.
• This is the main reason that it is difficult to implement web site that react intelligently to user input.
• This shortcoming of HTTP is being addressed in a number of new technologies, including ActiveX, Java, JavaScript and cookies.

• Errors on the Internet can be quite frustrating - especially if you do not know the difference between a 404 error and a 502 error.
• These error messages, also called HTTP status codes are response codes given by Web servers and help identify the cause of the problem.
• For example, "404 File Not Found" is a common HTTP status code. means the Web server cannot find the file you requested.
• This means the web page or other document you tried to load in your Web browser has either been moved or deleted, or you entered the wrong URL or document name.

Thank you for reading my post, if you like my post then share it to your friends.

   Browsers :-    

• The users enters the URL of the resource to be fetched on the address bar of the browsers.
• The Prefix of the URL explains the method to interpret the URL. Most of the URLs enable the recourse's to be retrieved Hypertext Transfer Protocol while some web browsers also supports prefixes like FTP i.e File Transfer Protocol.
• HTML script is passed to the browser for interpretation . Interactive script may be written using a scripting language like java script or VB script.
• The browser interprets text, images, videos and interactive script.
• The browsers allow users to open multiple tabs or windows for accessing multiple information resources at the same time. Browsers may include popup blockers which do not allow windows to open without users's permission 
• All browsers provide backward and forward buttons to navigate previous and next resource.
• History of the browsers keeps a list of previously visited web resources.
• Refresh or reload help to reload the current document in the browser.
• Stop button can be used to cancel the action on loading the resources.
• Home button enables the user to return to the website's home page.
• Search bar is used to allow user to input terms into the search engine.
• Status bar displays the progress of loading the current resource and also the URL of links when the cursor is moved over them.

Features of some popular browsers are discussed below.

1) Internet Explorer 

Internet Explorer commonly abbreviated as IE is a graphical web browser developed by Microsoft and included as a part of Windows operating system since 1995. The browser finds an upgrade with every upgraded windows version the latest being Internet Explorer 11 which can be downloaded as a free update for Windows 7- 64 bit, XP and above. Internet Explorer 11 features in windows 8.1 and was released on October 17, 2013.

Features of Internet explorer include,

• IE uses component based architecture built using Component Object Model (COM) technology.
• Internet Explorer exposed COM interfaces to allow add-on functionality to the browser. Web pages can be integrated with ActiveX controls for extending the content capabilities e.g. Adobe Flash Player and Silver light which can be installed locally.

• IE offers zone-based security and applies zone based restrictions.
• Versions of Internet Explorer support HTML 4.01 and X HTML, CSS Level 1 and 2, XML 1.0, SVG and Jscript.
• Allows organizing favorites in form of images which can be used as bookmarks.
• Internet Explorer allows tabbed browsing, Pop-Up blocking and provides user interface for FTP.
• IE caches visited pages in the Temporary Internet File folder where the content is indexed allowing quick offline access.
• IE can be configured using Group Policy, Administrators of Windows Server Domains can apply and enforce settings to change the user interface as desired. Policy settings can be configured for each user and each system. IE provides support for Integrated Windows Authentication.
• It allows grouping of sites based on conditions like editable and non-editable Internet or Intranet based site and the restrictions apply to all sites in the zone.

2) Netscape Navigator

• Netscape Navigator was a proprietary browser based on Mosaic web browser developed by Netscape and extensively used in 1990s.
• It was one of the most popular browser until 2002 as it was able to handle scripting languages like Java script. It was then discontinued from the market as other browsers took over the market of Netscape
• The evaluation copies i.e. beta versions 1.0 and 1.1 of the browser were available for free download from November 1994.
• Netscape Communicator suite was developed in 1997 is a successor of Netscape Navigator and was a base for Mozilla Application Suite which is popularly known as SeaMonkey.
• Netscape's Mozilla suite became a base for developing the most commonly used browser, Mozilla Firefox.

3) OPERA

• Opera is a browser and Internet suite developed by Opera software. It is one of the fastest and smallest browsers.
• The browser handle common internet related functions such as displaying web pages, sending and receiving emails, online chatting, downloading files and browsing through web resources.
• Opera is compatible with operating systems like Microsoft Windows, Mac and Linux and is offered for download for personal computer. Editions of Opera are available for Android and iPhone devices. 

 Features of Opera Include

1. Tabbed browsing
2. Page Zooming
3. Mouse Gestures
4. Download Manager
5. Built-in phishing
6. Malware protection
7. Strong Encryption
8. HTTP cookies

4) Firefox

Firefox in a freely available, open source web browser by Mozilla Application Suite. It is managed by Mozilla and is second most widely used browser after Chrome.

      Firefox uses Gecko layout engine, which is known to implement most current web standards. The latest Firefox features incremental find, live bookmarking, a download manager, private browsing, and location-aware browsing (also known as "geolocation") based exclusively on a Google service. The code is based on Mozilla code and is available for Windows 98, Windows 2000, Windows XP, Windows Vista, Mac OS and Linux. Latest version released officially is 49.0.2

Some features of Firefox included in the new version are:

• Improved look and feel : allows themes to dress up your browser 
• TraceMonkey JavaScript Engine: for better scripting and performance
• Compatibility for more than 70 languages: translations also available
• Provides support for HTML 5 audio, video and canvas elements: allows web developer to create animations 
• Provides support for all most all downloadable fonts : allows automatic installation of fonts which the website was designed to display 
• Allows private browsing: provides tools for controlling private data 
• Supports all the new web technologies : CSS media queries, JavaScript. query selectors, HTML 5 local and offline storage, now transformations and properties 
• Improved text rendering : rendering scripts and other languages in remarkably seamless way 
• Native JSON support 
• Pop-Up blocker : allow to create list of trusted and choice to view blocked Pop-Up
• Search suggestions : provide suggestion while searching by prompting allowing search bar for conversions and calculations 
• Location Aware Browsing: allowing to share your location known a geolocation exclusively based on Google services
• Incremental find : Provide real-time suggestions to progressively search for a filter through text
• Live bookmarking : Supports RSS feeds and bookmarks tool for frequently used web site and also used Firefox extensions with bookmarks

5) Chrome

 Chrome is a Web browser by google. Chrome is one of the first browser to incorporate machine translation wit the browser itself, without any requirement of additional plugins or extensions. Presently it is one of the most popular web browser due its features which includes :

• SIMPLICITY :   The browser window is simple, well-structured and streamlined. Moreover, Chrome includes all features that are designed for efficiency and ease of use like provision to search and navigate from the same window  and arrange tabs for browsing as per users need.
• SPEED : Chrome is designed for speed and efficiency. It has quick start-up from the desktop is efficient in rendering web pages and running complex web application.
• SECURITY : Chrome is designed with build-in safety and security features of auto update of latest security updates, phishing and malware protection. 

6) Mozilla

• Mozilla is not a web browser. It is a framework used for building better web  applications using standards. Mozilla is a open source project developing a complete set of web application including browsers, e-mail, news, chat and more.
• Mozilla is a term used in relation to Netscape Communication Corporation and its related application software, the Mozilla.org group and its success the Mozilla foundation.
• Mozilla originally describes three distinct entities : 

1. The Codename for Netscape Navigator Software project 
2. The official and original name of Mozilla Application Suite, now known as SeaMonkey
3. The mascot of Netscspe

• Products of Mozilla include 

1. Firefox : the most popular browser used today 
2. Thunderbird : Secure, fast and easy to use email 
3. SeaMonkey : browser, e-mail, chat and edit all in one application 
4. Bugzilla: a bug tracking tool 
5. Camino: a web browser for Macintosh 
6. Lightning and Sunbird : Calendar organizing extension

   Thanks for reading my post if you like this post then share it on your friends.