The Fn key (FuNction key) is a special key found primarily on notebook computers. Not to be confused with the Function Keys (typically F1-F12 on a regular desktop keyboard) the Fn key is a modifier key designed to give keyboard buttons a secondary function. It is common, for example, for notebook computers to have symbol labels on their top row numeric keys designating system functions accessible via the Fn key (e.g. the 1 key + FN yields monitor dimming or the 5 key + FN turns the Wi-Fi on and off).
In addition to the standard function keys on a keyboard (typically F1-F12), many modern keyboards include special function keys that are specifically designated for a given purpose, such as controlling the computer’s multimedia functions, hibernating the computer, opening specific folders such as My Documents, or otherwise providing one-button access to individual functions.
The function keys, typically labeled F1 through F12, are hardware keys on a computer keyboard reserved by the operating system or the current application to perform a given function. Common function key assignments include F1 to open the help file and F5 to refresh the content of the current pane (such as in a file explorer or web browser).
An email storm is when a very large volume of email messages are sent within a very short span of time. This has the potential to temporarily cripple both the sending and receiving mail servers. Although email storms may be generated by viruses that have gained access to user’s email clients (or even the email server itself), some of the largest mail storms have been generated by human error–typically when a mailing list is improperly configured and a single user is able to reply-all to tens of thousands of other list recipients.
The at sign (@), originally and traditionally called the ampersat, is a symbol used to separate the user from their domain within an email address, such as firstname.lastname@example.org, where the user is “admin” and the domain is “google.com”.
Resolution is a designation of the number of discrete elements an electronic or printed image is comprised of. In the case of displays (both large displays like HDTVs and small displays like those found on smartphones), the resolution is generally described in terms of the horizontal and vertical resolution. An HD monitor or TV, for example, has 1920 pixels running from side to side and 1080 pixels running from top to bottom. Although when discussing computer monitors and displays it is common to refer to the horizontal x vertical pixel count (as in the previously described 1920×1080 monitor), it is more common to talk about smartphone and other small displays in terms of Pixels Per Inch (PPI), which is another way to describe the resolution with an emphasis on how many pixels are in a given area (and thus how sharp and realistic the image is).
Just like DPI (Dots Per Inch) refers to the resolution of a printer’s output, PPI (Pixels Per Inch) refers to the resolution of a display screen. Historically, the PPI of computer displays was fairly low (the CRT monitors that dominated the computer display market up until the early 2000s, for example, generally had a PPI of around 60-100). The introduction of LCDs pushed the PPI above 100, and the PPI value of displays large and small have been increasing ever since (the Retina Display on the iPhone has a PPI of 326, and the HTC One sports a PPI of 468).
DPI is a common term used primarily in regard to printers and their output. It stands for Dots Per Inch and represents the resolution number of dots per inch in digital printing. The actual print resolution can be calculated by squaring the DPI number. Thus a printer with 100 DPI rating is capable of printing 10,000 dots per square inch, and a printer with a 1200 DPI rating is capable of printing 1,440,00 dots per square inch.
System-on-Chip designs have been pivotal in the development of powerful but energy efficient mobile electronics. Compared to a traditional computing system where functions are performed by discrete components (the CPU, GPU, sound processor, etc.), the SoC design packs everything onto a single chip. It is this miniaturization that allows a single chip in a modern smartphone to handle the core processing needs of the device as well as decode video, audio, and manage the extras on the device like motion sensors and cameras.
Vampire devices are electronic devices that still draw power even when the device appears to be off. In some cases the the draw is quite small as is the case with an electronic transformer which carries a steady 1 watt load when the device attached to it is turned off. In other cases the draw can be surprisingly high, as is the case with many cable boxes and other media peripherals that consume a significant amount of power when they are powered off (as they do a variety of tasks behind the scenes such as updating programming schedules, recording and downloading content, etc.)
Compared to a traditional blog–wherein posts are usually developed like essays–microblogs quite tiny, focused on short snippets of content and typically only include very short commentary and/or photo, video, or other multimedia elements.
A Blog (a portmanteau of “web” and “log”) is a website that contains stories and updates in reverse chronological order–the most recent entries appear at the top of the front page, and you browse backwards to move through the past articles. Blogs exploded in popularity the late 1990s with the advent of sites like Open Diary, Live Journal, and Blogger, which made it easy for individuals without web design experience or their own web host to have a personal blog.
Ultrabooks are high-end subnotebooks. Although the term has become synonymous with very lightweight yet full size laptop computers, it’s actually a trademark of computer company Intel and has specific criterion. The specifications cover battery life (5 hours or better), height (21 mm or thinner), time from hibernation resume (7 seconds or better) and, as you would expect, and Intel processor.
Netbooks are a class of subnotebooks. Introduced in late 2007, the tiny laptops are optimized for long battery life, low weight, and cost. Netbooks typically feature a screen ranging from 6-12″ in size, weigh around 2 pounds, and have 5-10 hour battery run times.
Subnotebooks are a class of portable computers designed to be smaller and lighter than a typical laptop computer, yet still run a full fledged operating system (such as Windows 8) and not a lightweight mobile-device operating system (such as Windows CE).
Peer-to-Peer (P2P) systems rely on direct system-to-system connections without a central infrastructure or server system facilitating the transmission of data or resources. P2P systems are utilized in situations where it is ideal to distribute loads across many users. In the case of BitTorrent (a type of distributed file sharing system), files are not stored on a central server, but instead are shared piece-by-piece in a distributed network composed of many users. This makes it easy to get popular files quickly and it protects the network from being shut down by outside authorities.
Radio buttons are a special type on-screen button found within application user interfaces. A radio button functions such that if you select one of the available options (say, printing in color instead of black and white), any other entry you made will be automatically deselected.
Color space is an abstract mathematical system used to describe colors using numerical values. While there are dozens of color space models, the two the average person comes in contact with on a day to day basis are RGB and CMYK. The RGB (Red Green Blue) color space is the color space used for computer monitors and all derivative screen types (tablets, smartphones, etc. all have RGB-based screens). CMYK (Cyan, Magenta, Yellow, and blacK) color spaces are used for printing. Whether on a home printer or high end dye-sublimation printer, those four colors are combined to create millions of different shades.
Televisions, computer monitors, phone and tablet displays, and other display screens use RGB color (all the colors you see via that display are composed of tiny red, green, and blue pixels adjusted to varying degrees of intensity to create a wide range of potential colors). Another way of saying this is that computers and related equipment use an RGB color space.
Web Crawlers, also known as Web Spiders, are programs that search for information on the World Wide Web. Web Crawlers are most widely employed by search engine companies and are used to create ever-growing indexes of web pages and their content. At its most elementary, a Web Crawler visits a known web page and then explores all the links on that web page (discovering new web pages in the process and repeating the sequence on them). Content that is not accessible to Web Crawlers is known as the Deep Web.
The Deep Web is web-based content that is not found in search engine results. Unlike Darknets, wherein the content is explicitly encrypted and kept from public view, most of the Deep Web content is invisible to search engines and their users simply because there are no links pointing the content. For example, if you created a website and never published the individual URLs of the page or linked to them from a publicly accessible main page, the chances that a search engine would find and index those pages are next to zero.
A Darknet is a network within a network operated expressly to facilitate the distribution of files, information, and communications while concealing the identity of participants. The content of the Darknet is not accessible to those outside of the Darknet and/or not the specific intended recipient of the communication. Examples of modern Darknets include the TOR network and Freenet.
TOR, or The Onion Router, is the world’s largest implementation of onion routing communication techniques. The TOR system is composed of thousands of volunteers around the world who run TOR proxy servers. When someone connects to the TOR proxy network, their communications are encrypted and passed through a series of TOR proxies. Any TCP-based application that supports standard SOCKS proxy protocols can be connected to the TOR network.