ASCII art is artwork created using the set of 128 symbols in the ASCII character set (English letters, numbers, and symbols). By aligning various characters the illusion of or the symbolic representation of an image is achieved. While many examples of ASCII art are multi-line, even a simple combination of characters, such as <(o.o)> , can yield a recognizable pattern.
ASCII, the American Standard Code for Information Interchange, is a character encoding scheme based on the English alphabet that encodes 128 characters (numbers, upper and lower case letters, as well symbols and control codes), into 7-bit machine readable binary integers.
Traceroute is an internet utility that performs a function exactly like its name implies: it traces the route data takes from the local computer back to the remote host. The utility is useful for a variety of diagnostic tasks such as establishing where in a route the connection is lost and how long the route is.
A newbie, alternatively spelled newb or noob, is a neophyte in a given pursuit. The term refers to the lack of skills, experience, and understanding of conventions the individual has in the area in question. Thus one can be a “newbie” to the world of competitive real-time strategies or tennis without being considered generally unskilled or incompetent.
Expansion cards are add-on circuit boards that expand the functionality of a computer. While there have been numerous variations on expansion card designs going back to the 1970s, the current standard is the PCI/PCI Express format. Computer motherboards (excluding laptops and very small form-factor micro desktop models) have expansion ports that allow you to add in additional hardware in order to add or improve a wide variety of functions on the computer such as better sound, additional ports for USB devices, upgrading to a better quality Ethernet card, and more.
In computer architecture, a bus is a communication system that transfers data between other components. Bus systems can be so small and buried in the hardware as to be invisible to the end-user (such as the address bus found within the CPU’s architecture) or can have obvious manifestations that the end user can interact with such as USB (Universal Serial Bus), the ubiquitous computer input connection.
In computer security, a man-in-the-middle attack is a type of attack that relies on the attacker’s ability to temporarily control or divert electronic communications so that they could observe and/or alter the communications. An analog equivalent of a man-in-the-middle attack would be the diversion of mail to a drop address, wherein the malicious recipient could read/alter the mail before sending it on to the correct mailing address.
Spoofing is the process by which a computer is misrepresented on the network as another computer. Spoofing can be done at the hardware level (e.g. MAC address spoofing) or at the TCP/IP level (e.g. IP address spoofing). The primary purpose of spoofing is to allow the unauthorized computer to gain access to a secure network wherein the security is provided by verification of a hardware or IP address. If a Wi-Fi node is locked down to only specific pre-approved MAC addressed, for example, a malicious user seeking to gain entry would need to spoof a valid MAC address to connect to the node.
Data modification is a typical component of network-based computer attacks. Either the data transmitted by the local computer or transmitted back from the remote computer is altered in some fashion. Strong encryption between the local computer and remote computer ensures that the data remains unobserved or altered.
In network security, sniffing is the act of examining network traffic. This is the digital equivalent of eavesdropping on a conversation or telephone call; all unencrypted traffic on the network is visible to anyone with access to the network and appropriate tools to examine the packets of data passing by.
Fault Tolerant Computing is a sub-division of computer design and construction focused on building computer systems that are highly resistant to failure. Such systems typically have redundant and compartmentalized hardware system so that in the event of any hardware failure the system may either be 1) kept online or 2) be shut down gracefully.
In computing, a heartbeat is a tiny exchange between computers, typically used in a server environment where stability and uptime are critical, that checks to make sure all systems on the heartbeat network are available and operational. The operation is called a heartbeat because the exchange happens twice per second and mirrors the regularity of a beating heart.
FLOPS, or FLoating point Operations Per Second, is a measurement of floating point calculations. This measurement is typically used to reference the performance of super computers as it is a better indicator of the performance and computing power of super computer array than referencing the collective processing power of the array. Thus you’ll frequently hear a super computer discussed in terms like 100 teraflops (100 trillion FLOPS) instead of the speed of the processor like one references when talking about desktop and mobile computers.
Name resolution is the process by which human-readable locators are converted into machine-usable locators used by computer networks, databases, and other machine-based applications. Every time you type www.howtogeek.com, for example, into your web browser, you are initiating a name resolution wherein the human-readable address for How-To Geek is translated, via DNS servers, into the IP address of the How-To Geek servers.
Before centralized DNS servers, computers used a local text document, known as a HOSTS file, as a reference to link IP addresses to domain names. Although HOSTS files are no longer used as a primary domain reference, they are still included in operating systems as a way of locally manipulating the IP-to-domain resolution chain for various purposes like testing software.
A file viewer is an application designed to quickly view a file without requiring the user to open up the file in the application the file was originally created in. A common example of this arrangement is that of digital image files such as JPEGs–the vast majority of JPEG image files are opened in a file viewer of some sort and not in the application which originally created or altered the digital image.
File types are broad classes of digital files categorized by their general type. The document file type, for example, encompasses Rich Text documents, basic text files, and files created by Microsoft Word. The file type is different from an extension in that the extension describes the specific kind of file (e.g. a .RTF) and the type describes the class (e.g. document).
MPEG (Moving Pictures Expert Group) is a family of video compression standards that encompasses everything from DVD encoding to satellite video transmission. DVDs, for example, are encoded in MPEG-2, where as more modern HD video sources are encoded using MPEG-4.
H.264 is a popular video compression standard based on MPEG-4. It is widely used for both HD video sources like Blu-Ray discs and for streaming video from sites like YouTube using minimal bandwidth while maintaining quality video. While there other other H.X compression standards (like H.263), none have achieved the same level of widespread adoption as H.264.
The UHF (Ultra High Frequency) spectrum, or 700Mhz communication spectrum (technically 698-806Mhz), was historically used for television broadcasting. Starting in 2008, the FCC began auctioning off sections of the spectrum in anticipation of the 2009 switch from analog to digital TV broadcasts. Thanks to the suitability of 700Mhz spectrum broadcasts for long distance wireless communication, a significant portion of the available blocks were purchased by large telecommunication companies like Verizon Wireless and AT&T.
A thin client is a lightweight machine that offloads its processing and data handling tasks to a central machine. Under the thin client computing model, each thin client terminal the user interacts with is essentially just a front end that only handles rendering a local GUI for the user, while the actual computing happens on a central server somewhere else within the building or even in a remote location. While thin client computing has the obvious disadvantage of removing the actual processing power from the local machine, it has many advantages like ease of system maintenance, increased security, and, in some applications, significant cost savings over deploying a large network of more advanced PCs.
Within the designated Wi-Fi bands, such as the 2.4Ghz band, there are specific channels Wi-Fi access points may use. Although there are 14 available channels in the 2.4GHz band, each individual channel has a spread of approximately 22Mhz, which significantly overlaps surrounding channels. As such, multiple devices set to adjacent channels in a small physical space (such as an apartment block) will interfere with each other. For example, if you are having problems with Wi-Fi connectivity and sustained data transmission through your Wi-Fi router, it is recommended to check the operating channels of all detectable Wi-Fi access points to ensure your Wi-Fi access point isn’t operating on the same or adjacent channel as nearby access points. You can read more about identifying and changing your Wi-Fi channel here.