The Internet and the Web

File transfer protocol(FTP)

The File Transfer Protocol is a software standard for transferring computer files between machines with widely different operating systems. It belongs to the application layer of the internet protocol suite.

Objectives:

1. To promote sharing of files (computer programs and/or data).
2. To encourage indirect or implicit use of remote computers.
3. To shield a user from variations in file storage systems among different hosts.
4. To transfer data reliably and efficiently.

Disadvantages:

1. Passwords and file contents are sent in clear text, allowing eavesdropping which may be unwanted.
2. It is hard to filter active mode FTP traffic on the client side by using a firewall, since the client must open a random prot in order to make the connection. This problem is largely resolved by using passive mode FTP.
3. It is possible to tell a server to send to an arbitrary port of a third computer.

Plug-ins

A plug-ins is a computer  that can interact with another program to provide a certain function. Typical examples are plugins to display specific graphic formats for instance, SVG if the browser doesn´t include this format by default, to play multimedia files, to encrypt or decrypt email e.g. PGP, or to filter images in graphic programs. The main program which is a web browser or an lemail program provides a way for plugins to register themselves with the program, and a protocol by which data is exchanged with plugins.

Filters

A filter(software) is a computer program to process a data stream. Some operating system such as Unix are rich with filter programs. Even Windows has some simple filters built in to its Command shell, most of which have significant enhancements relative to the similar filter commands that were available in MS-DOS.

Internet Security Suit

A suite of utilities for maintaining the security of a Windows PC. For instance, antivirus, personal firewall, spam blocker and popup blocker which you have it in your computer.

 

Wiki

A wiki is a website that allows the easy creation and editing of any number of interlinked webpages via a web browser using a simplified markup language. Wikis are powered by wiki software and are often used to create collaborative wiki websites, to power community websites, for personal note taking, in corporate intranets, and in knowledge management systems.

 Javascripts

Javascript is an implementation of the ECMAScript language standard and is used to enable programmatic access to computational objects within the host environment. JavaScript is primarily used in the form of client-side Javascript , implemented as part of a web browser in order to provide enhanced user interfaces and dynamic websites. However, its use in applications outside web pages—for example in PDF-documents, site-specific browsers and deskstop widgest is also significant. Examples of javascript is HTML.

Applets

An applet is a program written in the Java programming language that can be included in an HTML page, much in the same way an image is included in a page. When you use a Java technology-enabled browser to view a page that contains an applet, the applet's code is transferred to your system and executed by the browser's Java Virtual Machine (JVM).

HTML

HTML which stands for Hypertext Markup Language, is the predominant markup language for web pages. A markup language is a set of markup tags, and HTML uses markup tags to describe web pages.

URL

URL stands for Uniform Resource Locater is a Uniform Resource Identifier(URI) that specifies where an identified resource is available and the merchanism for retrieving it. The best-known example of the use of URLs is for the addresses of web pages on the World Wide Web, such as http://www.example.com.