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Wi-Fi

Wi-Fi
Wi-Fi, also spelled Wifi or WiFi, is a technology that allows an electronic device to exchange data or connect to the internet wirelessly using 2.4 GHz UHF and 5 GHz SHF radio waves. The name is a trademark name, and was stated to be a play on the audiophile term Hi-Fi. The Wi-Fi Alliance defines Wi-Fi as any "wireless local area network (WLAN) products that are based on the Institute of Electrical and Electronics Engineers' (IEEE) 802.11 standards".[1] However, since most modern WLANs are based on these standards, the term "Wi-Fi" is used in general English as a synonym for "WLAN". Only Wi-Fi products that complete Wi-Fi Alliance interoperability certification testing successfully may use the "Wi-Fi CERTIFIED" trademark. Depiction of a device sending information wirelessly to another device, both connected to the local network, in order to print a document. Wi-Fi can be less secure than wired connections (such as Ethernet) because an intruder does not need a physical connection. Related:  Gadgets

LG Optimus Black The LG P970 Optimus Black is a smartphone designed and manufactured by LG Electronics and was released in 2011. At 9.2 mm in thickness, it was LG's thinnest smartphone at the time of its release, and is slightly thinner than the iPhone 4. The LG Optimus Black features a WVGA NOVA display which is brighter than competitor displays with brightness officially claimed to be over 700 nits. Availability[edit] North America[edit] In the United States, the LG Optimus Black is offered by multiple wireless carriers known by their individual brandings. Sprint and Boost Mobile released it as the LG LS855 MarqueeNET10/Straight Talk offer it as the LG L85C though it retains the "Optimus Black" name.US Cellular offers it as the LG US855 MajesticKT Korea Offers it as the LG KU5900Other regional carriers offer it as the LG 855 Ignite In Canada, the LG Optimus Black Skype Edition variant is offered by Telus Mobility as a special edition in collaboration with Skype. Software updates[edit] See also[edit]

Java Virtual Machine Overview of a Java virtual machine (JVM) architecture. Source code is compiled to Java bytecode, which is verified, interpreted or JIT-compiled for the native architecture. The Java APIs and JVM together make up the Java Runtime Environment (JRE). A Java virtual machine (JVM) is a process virtual machine that can execute Java bytecode. It is the code execution component of the Java platform. Overview[edit] A Java virtual machine (JVM) interprets compiled Java binary code (called bytecode) for a computer's processor (or "hardware platform") so that it can perform a Java program's instructions. JIT compiling, not interpreting, is used in most JVMs today to achieve greater speed. JVM languages[edit] Bytecode verifier[edit] The JVM verifies all bytecode before it is executed. Branches are always to valid locationsData is always initialized and references are always type-safeAccess to private or package private data and methods is rigidly controlled. Bytecode instructions[edit] Heap[edit]

Mirror A first surface mirror coated with aluminum and enhanced with dielectric coatings. The mirror was constructed from an optical flat with a flatness of /20, which equates to a surface deviation less than 31.6 nanometers. Some mirrors also filter out some wavelengths, while preserving other wavelengths in the reflection. Mirrors are commonly used for personal grooming or admiring oneself (in which case the archaic term looking-glass is sometimes still used), decoration, and architecture. History[edit] A sculpture of a lady looking into a mirror, India The first mirrors used by people were most likely pools of dark, still water, or water collected in a primitive vessel of some sort. The invention of the silvered-glass mirror is credited to German chemist Justus von Liebig in 1835.[18] His process involved the deposition of a thin layer of metallic silver onto glass through the chemical reduction of silver nitrate. Manufacturing[edit] Types of glass mirrors[edit] Effects[edit] Mirror image[edit]

Smart Phone WebKit WebKit is available under a BSD-form license[11] with the exception of the WebCore and JavaScriptCore components, which are available under the GNU Lesser General Public License. As of March 7, 2013, WebKit is a trademark of Apple, registered with the U.S. Patent and Trademark Office.[12] Origins[edit] According to Apple, some changes involved OS X-specific features (e.g., Objective-C, KWQ,[15] OS X calls) that are absent in KDE's KHTML, which called for different development tactics.[16] Split development[edit] The exchange of code between WebCore and KHTML became increasingly difficult as the code base diverged because both projects had different approaches in coding and code sharing.[17] At one point KHTML developers said they were unlikely to accept Apple's changes and claimed the relationship between the two groups was a "bitter failure".[18] Apple submitted their changes in large patches containing very many changes with inadequate documentation, often to do with future additions.

Freehold From Wikipedia, the free encyclopedia Freehold may refer to: General real estate law (modern British, pertaining to any land so designated) British law regarding manors (modern and archaic) customary freehold, privileged copyhold or copyhold of frank tenure Church of England Vernacular use (common speech), British middle ages Land owned privately, rather than by the Crown or the village commons Colonial America Land owned without incurring debt, not subject to (most) edicts by colony leaders or colonial proprietary governors. Places Former colonial freeholds (America) In St. Fiction Ships

IEEE 802.11n-2009 IEEE 802.11n-2009, commonly shortened to 802.11n, is a wireless networking standard that uses multiple antennas to increase data rates. It is an amendment to the IEEE 802.11-2007 wireless networking standard. Its purpose is to improve network throughput over the two previous standards—802.11a and 802.11g—with a significant increase in the maximum net data rate from 54 Mbit/s to 600 Mbit/s (slightly higher gross bit rate including for example error-correction codes, and slightly lower maximum throughput) with the use of four spatial streams at a channel width of 40 MHz.[1][2] 802.11n standardized support for multiple-input multiple-output and frame aggregation, and security improvements, among other features. It can be used in the 2.4 GHz or 5 GHz frequency bands. 802.11 is a set of IEEE standards that govern wireless networking transmission methods. Description[edit] Data encoding[edit] Number of antennas[edit] The 802.11n draft allows up to 4 x 4 : 4. Data rates[edit] Wi-Fi Alliance[edit]

Mobile ad hoc network A mobile ad hoc network (MANET) is a self-configuring infrastructureless network of mobile devices connected by wireless. Ad hoc is Latin and means "for this purpose".[1] MANETs are a kind of Wireless ad hoc network that usually has a routable networking environment on top of a Link Layer ad hoc network. Types[edit] Vehicular Ad hoc Networks (VANETs) are used for communication among vehicles and between vehicles and roadside equipmentInternet based mobile ad hoc networks (iMANETs) are ad hoc networks that link mobile nodes and fixed Internet-gateway nodes. A mobile ad-hoc network (MANET) is an ad-hoc network but an ad-hoc network is not a MANET. Simulations[edit] There are several ways to study MANETs. Data monitoring and mining[edit] Security[edit] A lot of research has been done in the past but the most significant contributions have been the PGP (Pretty Good Privacy) and trust based security. Attack classifications[edit] See also[edit] References[edit] Further reading[edit]

Concealing objects in a book A hollowed out book, with bottle caps for scale. There are many real and fictitious occurrences of concealing objects in a book. Items can be concealed in books in a number of ways. Another type of concealment is the hiding of messages in the text or on a book's pages by printing in code — a form of steganography. Illicit chemicals may be smuggled by soaking individual pages with them. Books are used as a concealment device in part because they are readily available and inconspicuous in many settings. Methods of concealment[edit] Hollow Book Safes[edit] Hollow Book Safes prices can vary based on the cost of materials, additional features, and production resources used to create the functionality and aesthetics of a hollow book. The scale of gadgetry used to create the seal of a hollow book's closing properties have ranged from simple to complex. Many book safes are handmade. Steganography and hidden messages[edit] Messages can be hidden within a book using steganographic techniques.

WLAN BitTorrent (protocol) Programmer Bram Cohen, a former University at Buffalo graduate student in Computer Science,[4] designed the protocol in April 2001 and released the first available version on July 2, 2001,[5] and the final version in 2008.[6] BitTorrent clients are available for a variety of computing platforms and operating systems including an official client released by Bittorrent, Inc. As of 2009, BitTorrent reportedly had about the same number of active users online as viewers of YouTube and Facebook combined.[7][8] As of January 2012[update], BitTorrent is utilized by 150 million active users (according to BitTorrent, Inc.). Based on this figure, the total number of monthly BitTorrent users can be estimated at more than a quarter of a billion.[9] Description[edit] The middle computer is acting as a seed to provide a file to the other computers which act as peers. The file being distributed is divided into segments called pieces. When a peer completely downloads a file, it becomes an additional seed.

Refrigerator Food in a refrigerator with its door open A side-by side refrigerator with an icemaker A refrigerator (colloquially fridge) is a common household appliance that consists of a thermally insulated compartment and a heat pump (mechanical, electronic, or chemical) that transfers heat from the inside of the fridge to its external environment so that the inside of the fridge is cooled to a temperature below the ambient temperature of the room. Refrigeration is an essential food storage technique in developed countries. Lower temperatures in a confined volume lowers the reproduction rate of bacteria, so the refrigerator reduces the rate of spoilage. A refrigerator maintains a temperature a few degrees above the freezing point of water. History[edit] Refrigeration technology[edit] The history of artificial refrigeration began when Scottish professor William Cullen designed a small refrigerating machine in 1755. Schematic of Dr. Domestic refrigerator[edit] Freezer[edit] Styles of refrigerators[edit]

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