E-commerce (electronic-commerce) refers to business over the Internet. Web sites such as Amazon.com, Buy.com, and eBay are all e-commerce sites. The two major forms of e-commerce are Business-to-Consumer (B2C) and Business-to-Business (B2B). While companies like Amazon.com cater mostly to consumers, other companies provide goods and services exclusively to other businesses. The terms "e-business" and "e-tailing" are often used synonymously with e-commerce. They refer to the same idea; they are just used to confuse people trying to learn computer terms.
It's hard to remember what our lives were like without e-mail. Ranking up there with the Web as one of the most useful features of the Internet, e-mail has become one of today's standard means of communication. Billions of messages are sent each year. If you're like most people these days, you probably have more than one e-mail address. After all, the more addresses you have, the more sophisticated you look...
E-mail is part of the standard TCP/IP set of protocols. Sending messages is typically done by SMTP (Simple Mail Transfer Protocol) and receiving messages is handled by POP3 (Post Office Protocol 3), or IMAP (Internet Message Access Protocol). IMAP is the newer protocol, allowing you to view and sort messages on the mail server, without downloading them to your hard drive.
Though e-mail was originally developed for sending simple text messages, it has become more robust in the last few years. Now, HTML-based e-mail can use the same code as Web pages to incorporate formatted text, colors, and images into the message. Also, documents can be attached to e-mail messages, allowing files to be transfered via the e-mail protocol. However, since e-mail was not originally designed to handle large file transfers, transferring large documents (over 3 MB, for example) is not allowed by most mail servers. So remember to keep your attachments small!
Ethernet: the most common type of connection computers use in a local area network (LAN). An Ethernet port looks much like a regular phone jack, but it is slightly wider. This port can be used to connect your computer to another computer, a local network, or an external DSL or cable modem.
Encoding is the process of converting data from one form to another. While "encoding" can be used as a verb, it is often used as a noun, and refers to a specific type of encoded data. There are several types of encoding, including image encoding, audio and video encoding, and character encoding.

Media files are often encoded to save disk space. By encoding digital audio, video, and image files, they can be saved in a more efficient, compressed format. Encoded media files are typically similar in quality to their original uncompressed counterparts, but have much smaller file sizes. For example, a WAVE (.WAV) audio file that is converted to an MP3 (.MP3) file may be 1/10 the size of the original WAVE file. Similarly, an MPEG (.MPG) compressed video file may only require a fraction of the disk space as the original digital video (.DV) file.

Character encoding is another type of encoding that encodes characters as bytes. Since computers only recognize binary data, text must be represented in a binary form. This is accomplished by converting each character (which includes letters, numbers, symbols, and spaces) into a binary code. Common types of text encoding include ASCII and Unicode.

Whenever data is encoded, it can only be read by a program that supports the correct type of encoding. For audio and video files, this is often accomplished by a codec, which decodes the data in real-time. Most text editors support multiple types of text encoding, so it is rare to find a text file that will not open in a standard text editor. However, if a text editor does not support the encoding used in a text document, some or all of the characters may appear as strange symbols rather than the intended text.

End user-is the person that a software program or hardware device is designed for. The term is based on the idea that the "end goal" of a software or hardware product is to be useful to the consumer.

E-reader:An e-reader, or "e-book reader," is a portablehardware device designed for reading digitalpublications. These include e-books, electronic magazines, and digital versions of newspapers. Since textual data does not require a lot of storage space, most e-readers can store thousands of books and other publications. Just like an iPod can store an entire music library, a single e-reader can store a large collection of books.
Dozens of different e-readers are available, but some of the most popular ones include the Amazon Kindle, the Barnes and Noble Nook, and the Sony Reader. These devices all support a wide range of eBook formats and can download content over a wireless network. Many e-readers have amonochrome display, often called "electronic paper," while others have a full-color backlit display. While the electronic paper displays do not provide color images, the screen appears more like a paper page from a book, and it can be easily viewed in bright sunlight.
Tablets, such as the Apple iPad, the BlackBerry PlayBook, and the Amazon Kindle Fire are often considered e-readers, since they can be used for reading digital publications. However, it is more accurate to refer to these devices as tablets that can be used as e-readers since they are not designed primarily as digital readers. Tablets offer more capabilities than e-readers, but e-readers are often better suited for just reading e-books.

expansion card- a printed circuit board that can be installed in computer to add functionality to it.

Export: A command usually found within a program's File menu (File → Export...). It is similar to the File → Save As... command, but is typically used for more specific purposes. For example, instead of simply saving a file with a different name or different format, "Export" might be used to save parts of a file, create abackup copy of a file, or save a file with customized settings.
Since the Export command is only used for specific purposes, it is not available in all applications. For example, most text editors do not include an Export feature because text documents do not contain anything specific to export. Instead, the Export command is often found in multimedia programs, like photo and video editing applications. For example, Adobe Photoshop includes an Export command that allows users to export vector paths within an image as Adobe Illustrator files. Apple QuickTime Player allows users to export videos to multiple formats and provides advanced options for choosing the compression type, frame rate, video dimensions, and other settings. QuickTime's "Save As..." command only allows users to save movies in the standard QuickTime (.MOV) format.