HAPTIC FEEDBACK (A/K/A/ HAPTICS):  A new media that deals with the sense of touch.  By using the sense of touch in a user interface, it is possible to use a mouse or keyboard without actually viewing the keyboard. In cellphones, for example, vibration sensations take the place of a ring tone.  In a PDA or Blackberry, vibrations or noises can make the user aware that a representation of a physical button has been pressed.  The resistive force that some “force feedback” joysticks provide is another form of haptic feedback.  Newer haptics currently being developed are that use a process called “controlled static cling” to simulate the up-and-down pressing of a keyboard key (Pacinian), a process called “artificial muscle” where current causes electrodes to expand and contract, useful in gaming consoles (Bayer MaterialScience), a special coating which changes the attractive forces between human skin and a screen, simulating vibrations, clicks and textures (Senseg), and even “morphing screens” in which keyboards and game control knobs literally grow out of a screen, as needed, then fade away (Tactus Technology).  Look for these features to come out on computers and cell phones the next few years.  See also, Virtual Reality.

HARDENED:  Made more secure, either by software and/or hardware.

HASH/HASHING: (1) The transformation of a string of characters into a usually shorter fixed length value or key (an integer - say 02 to represent “Joe Kelly”) still representing the usual string. (2) Hashing is often used to index and retrieve items in a database (creating a “hash table”) because it is faster to find the item using the shorter key.  (3) It’s also often used in encryption.  Sometimes encryption also uses a “salt” which is a random bit of information to complicate so-called dictionary attacks attempting to decipher passwords. (4) Finally, the hash symbol (“#”) is placed before tweets to indicate that one is following a topic on Twitter.  This is known as a “hash tag”.

HAYES: See Modem.

HDD: “Hard Disk Drive” - the device that holds all of the information on your computer, including the operating system (“OS” such as Windows).  Traditionally, the drive is comprised of a hard metal disk (“platter”) and an actuator arm that is magnetically maneuvered across the spinning disk in order to access the information stored on the drive.  The data is stored even when the hdd is off, unlike cache or RAM.  For a more extensive discussion about hard drives and their operation, click HERE.  Newer solid state drives (“SSDs”) have no moving parts.

HD DVD: Stands for High-Definition/Density Digital Versitile Disk.  A high density DVD designed by Toshiba in the 1990s for storing hi-gh definition video such as movies.  Toshiba abandoned this format in 2008, announcing that it would support Blu-ray technology and would no longer develop HD DVD players or drives.  So it’s a lot like the BetaMax losing the video wars to VHS tapes in the 80’s; but don’t despair, it’ll take quite some time to disappear - and Blue-ray players aren’t selling nearly as fast as the industry had hoped.  See also CDs, DVDs, etc. 

HDMI: High Definition Multimedia Interface.  A type of cable and connection specification that combines both video and audio into a single cable.  Becoming a standard connection on more recent TVs; Blu-Ray will only work with HDMI connections.  One of the leading manufacturers of HDMI is Monster Cable. Click HERE.

HDR: High Dynamic Range.  A method of taking striking photographs in which the photo is shot three times, at three different exposures (low, regular and high), and then stacked to create one image.  This creates a sharp image that looks closer to what the human eye sees, as the varying highlights and shadows are all accounted for.  Most HDR photos are taken with dSLR cameras or some smartphones and then edited in Photoshop.

HEAT SINK: A device, usually made of aluminum, and often with “fins”, that is used to dissipate the intense heat generated by various types of computer chips.  Also sometimes called a “heat spreader”.  Usually it is affixed to the CPU chip with clips and thermal grease.  When included with a fan, called a HSF (“heatsink/fan combo”).

HELLMAN TRADE-OFF: In cryptoanalysis, this is a probabilistic algorithm  invented by Martin Hellman comparing the time available for searching for the key against memory or key solution space, by using a pre-computed table for block (later stream) ciphers. This type of lookup table was later refined into Rainbow Tables, commonly used to recover a  plaintext password generated by a hash function.

HEURISTIC:  Basically, anti-spyware programs’ ability to respond to unknown attacks.  Behavioral-based, using trial-and-error and experimentation to rapidly come to an optimal solution.  A term applied to methods of solving problems on the basis of extrapolating from solutions to previous similar problems, a sort of “educational” process.  For example, heuristic anti-spyware programs may locate and remove new spyware on the basis of examining patterns for previous spyware code, learning from its past experience.

HFS: Heirarchal File System a/k/a “Mac OS Standard,” the Macintosh file system.  Later, Apple introduced Mac OS Extended (“HFS+”) which supported unicode and increased file size from 2Gb to 16Tb.  Later versions added journaling,  and case-sensitive file names under the HSFX option.  See File System.

HIJACKING: See “jacking”.  Also, Spyware.

HOLLORITH: Herman Hollerith, an American statistician (1860-1929) who developed punched cards as the means for storing and processing data, founder of the company which would become IBM.  Widely regarded as the “father of automatic computation.”  See “punch card” for more.

HOLOGRAM: A method of producing a three-dimensional image of an object by photographic projection. The theory was invented by Dennis Gabor in 1947 and made possible by the development of laser technology. The term is derived from the Greek words “halos” (whole) and “gamma” (message).  Unlike either 3-D or Virtual Reality, a hologram is a true three dimensional image, not a simulation of spatial depth or requiring any special viewing device.

HONEYPOTS: A/K/A base station clones, evil twin - see, Spyware.

HOP: The link between two network or Internet nodes or network devices.  Typically, an IP packet travelling from coast to coast via the Internet can “hop” through more than a dozen routers.

HOPPER: A set top box introduced by Dish TV in 2012 which can simultaneously record up to six programs at once then play them back on any TV in a home network.

HOST: (1) Any computer that has a live connection with the Internet.  As such, all computers on the Internet are peers to one another, and can act as either servers or clients.  The Internet is nothing more than a global network of hosts communicating back and forth.  All computers, or hosts, are equal on the Internet. See also, Internet, Peer to Peer. (2) A server computer, which runs software or stores data for access by the workstation computers connected to it.

HOTFIX: A Microsoft Windows fix for a specific issue, such as one caused by a Windows update and a specific item of software or hardware.  It cannot be downloaded but, rather, must be requested by e-mail directly from Microsoft, wich will, in turn, e-mail the Hotfix by return e-mail.

HOSTS FILE: A file in Windows (also Linux and Mac O/Ss) which is used as an optional means to direct TCP/IP traffic under special circumstances.  The file is not used during normal network operation.  In Windows, the file is usually an editable Notepad file in the Windows>System32>drivers>etc folder.  It’s purpose is primarily to prevent access to unintended Web servers which might contain advertising or inappropriate content and also to set up private, easy-to-remember "shortcut" names for servers on a local network. So, for example, you might install Adobe Photoshop on your computer and the Windows Hosts file will contain the names of the Adobe update servers so that you will positively connect to them and not similarly named servers which may provide spam or intrusions instead of the intended updates.

HOTKEY: A key which, when pressed itself or in combination with other keys on a computer keyboard, is programmed to run a macro or a link which is a shortcut to a desired result.  For example, you can program the % key to always type “joe” each time it is pressed.

HOTSPOT: Refers to the geograpic area encompassed by a WiFi access point.Anyone entering the hotspot can access the Internet from within it.  Hotspots may be static (as in an office or home) or portable (various cell phones are self-contained hotspots for up to a certain number of devices.

HSDPA: High Speed Download Packet Access, a fast 3G broadband technology used by cellphones and PDAs.  See also, CDMA, GSM.

HTML:  “HyperText Markup Language”.  This is a computer language primarily used in developing websites.  Hypertext is a language that allows “linking” text; that is, when you click on highlighted (linked) text to take you somewhere else in the document or another document altogether.  The “markup” part of the definition refers to using markup tags to change the attributes (text size, bold, italics, placement, etc.) of text.  There have been numbered versions, the current version being HTML 4. HTML 5 is not yet a full WWW Consortium standard, but should be shortly, partly due to its inclusion in Firefox 3.5 and soon other browsers.  HTML 5 is actually a major innovation in web browsing, providing many of the same GUI interactions one gets from RIA (“rich Internet applications) and desktops.  Video is handled directly, rather than as a plug-in, for example.  Basically, HTML5 technology is a whole new class of web applications that support multimedia content and offline capability without the need for proprietary plug-in technology like Adobe’s Flash.  Apple has refused to support Flash in its products (iPad, iPhone, etc.) and has instead opted to use HTML5.

HTTP: Hypertext Transfer Protocol, one of the protocols (languages) used for transmitting data across the Internet.  HTTPS (Hypertext Transport Protocol Secure) is the protocol for accessing a secure web server for tasks such as credit card processing, bank statements, etc.  Using https in the URL instead of HTTP automatically directs the message to a secure port number (rather than the default web port number 80), where the session is them managed by SSL. You should always surf secure when using Wi-Fi hot-sport (https in Internet Exporer; in Firefox, a secure connection will turn the address box gold).

HUBS, SWITCHES & ROUTERS (also REPEATERS, AMPLIFIERS, BRIDGES):  Each of these hardware devices are used for networking computers, with varying capabilities.  The main differences between these three devices, which are frequently confused, is the degree of “intelligence” in each.  The least intelligent, expensive or complicated of the three devices is the “hub”. This “box” has several “ports” where computers are plugged in, and assures that every computer connected to a hub sees everything and every other computer connected to that hub.  It doesn’t know or care which computers it is interconnecting, and has no idea what information passes over the network.  Basically, a hub takes one cable and splits it into several other cables.  Of course, this causes “collisions” which can slow down the network.  But it’s inexpensive.   A switch is more intelligent and efficient than a hub because it has the ability to remember where particular “addresses” are. So, for example, if a switch sees traffic coming in on the second port for computer A, it will remember the address for computer A and not waste further time in the future scanning the entire network for computer A.  More intelligent switches are known as managed switches, which use Simple Network Management Protocol (SNMP) to  supply the owner with a variety of intelligence regarding traffic flow,  operating speeds and bandwidth potentials, providing control over each switch port, information about who can access the shared LAN as well as connection speeds and communication. A router is the most intelligent of the devices because it can actually be programmed to understand and then “route” the incoming data it is being asked to handle. Routers can also modify the data, for example, to “hide” the receiving computer behind a firewall. They also listen to see how busy the network may be, and “route” the signal in the least busy part of the network, if necessary.  Routers are increasingly popular because they allow users to “share” broadband internet connections so that many users may be simultaneously connected to the internet, viewing different web pages.  A gateway is used to route data between networks (even different types of networks, including your cable provider); simply, it’s your access out of your internal network.  This is different from a router, which only routes data between clients (computers)  on a single network. But many routers are also gateways, such as residential sharing routers which can share between computers on a network, but also are a gateway to the Internet through the router’s WAN port.  See also, repeaters (which amplify a signal over a  long network cable), signal amplifiers (which amplify a weak signal at its source) and bridges (which are actually “smart repeaters” because not only do they amplify the signal, they deliver the signals between the computers on either side of the box); see also LAN DIAGRAM.

HULU:  If you didn’t get the 2008 Superbowl commercial with Alec Baldwin where he described Hulu as “an evil plot to destroy the world,” here’s what it’s all about:  Hulu.com is a website publicly launched in March, 2008 that offers streaming video of current TV shows and movies from networks and studios in Flash and other video formats with limited commercial interruptions.  It is, however, supported through displayed commercials.  It is joint venture of NBC Universal and News Corp. (Fox) and, later (in 2009), Disney.  What does it mean?  While there is no English translation for the word, according to CTO Eric Feng, the name Hulu comes from a Chinese proverb meaning “holder of precious things” (referring to video clips, I suppose); literally the calabash gourd, a Chinese container for beverages.  CEO Jason Kilar adds that it’s just short, easy to spell and remember, easy to pronounce, rhymes with itself and is just plain fun, capturing the spirit of the service.  With the Comcast acquisition of NBC in December, 2009, it remains to be seen whether Hulu and other sites like it (e.g. Joost) can sustain their business model, so far without profit, without charging for viewing, at least to viewers outside of their subscription.

HYPERTEXT:  Generally, text with links to other text.  When text which is highlighted is clicked on with a mouse, it links to other text.  For example, the links highlighted in blue in this website are hypertext links.

HYBRID DRIVES:  This is a hard disk drive which is a combination of a SSD (which is entirely electronic, like a flash drive) and a conventional IDE or SATA drive.  Seagate introduced such drives back in 2007, but the lack of operating system support (remember Vista ReadyDrive?) and necessity for special drivers pretty much doomed the idea.  But the idea was a good one:  By marrying a small amount of non-volatile flash memory to a standard hard disk, it was possible to improve system boot and application startup times because the most used data was stored on the faster flash part of the drive.  Seagate didn’t give up, and in 2010 introduced the Momentus XT drive, which doesn’t depend on operating system support, doesn’t drain power or overheat, is fast and is reasonably priced, especially when compared to the high priced SSDs.  Seagate uses what it calls “Adaptive Memory”, which puts the frequently accessed data on the faster solid-state memory. The 7200 rpm drives are available for laptops now.

HYPER-V:  Stands for hypervisor technology, sometimes called virtual machine monitor (“VMM”), which is software on which multiple computers can run on a host computer, with the so-called hypervisor layer controlling the hardware and allocating resources to each VM operating system.  Hyper-V is the virtualization platform that is included within Windows Server 2008.  Microsoft also recently released a stand-alone version, called Hyper-V Server 2008.  Hyper-V is a Type 1 or “native” hypervisor, meaning that it has direct access to the physical machine’s hardware.  This is to be distinguished from Type 2 or “hosted”  virtualization products that have to run on top of a host operating system (e.g. Windows Server 2003) and which doesn’t have direct access to the hardware.

H.323:  This is a standard which provides a foundation for audio, video and data communications across IP based networks, including the Internet.  An alternative protocol to SIP, commonly used for VoIP applications like Skype and Vonage.

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