Fiber Optic cable: A cable made of glass not wire that uses pulses of light to transmit information. Fiber optic cable provides higher bandwidth and can transmit data over longer distances than copper wire and DSL. Telephone companies began to replace copper wire networks with fiber optic cable in the 1980s. An increasing proportion of the internet uses fiber optic cable, although television cable still provides the majority of internet access in the US (2019).

FTP (File Transfer Protocol) Client: A program that lets a user transfer a file from their computer to a web server so that it can be available or viewed online.

Full-Text Search: A search that examines every word in stored documents to find matches for the search criteria. Previous forms of search typically examined only metadata associated with documents, such as title, author, date of publication and subject classifications. Full-text search became more widely available with the mass digitization of texts that began in the 1990s. See also Google search; Image Search; Reverse Image Search.

Generous interface: A visual interface for search results that presents the scale and richness of a collection. Rather than a list of search results, a generous interface provides overviews to establish context and maintain orientation while revealing detail at multiple scales. Where browse-based interfaces present collections as alphabetical lists, the overviews in a generous interface are based on selected features (e.g. year, subject, color). Coined by Mitchell Whitelaw.

GIS (Geographic Information Systems): Software that combines a database and a mapping application to relate information to a location. ARC-GIS is the best known example of this software; it is a commercial product with a steep learning curve designed primarily for social scientists working with quantitative data. An open source alternative is QGIS. See also Web Mapping.

Georeferencing: Transforming place names and addresses into coordinates for mapping.

GIF: A lossless image file format now most commonly used for images containing animations. See also TIFF; Resolution; Pixel.

Github: An open source platform for sharing code and any other kinds of files.

GLAM: Acronym for Galleries Libraries Archives Museums.

Google Search: A search engine that conducts a text search of the index of the web created by Google’s web crawlers, with relevant results displayed as a list on a page. The algorithms that sort the results to place the most relevant at the top of the list look at language models to try to identify the meaning of the query, other search results with similar keywords, what other users have chosen from results for that search, sites linked to by other sites (Page Rank), the usability of sites and information about the person conducting the search such as location, search history, and search settings. Google does not provide more specific information on its algorithms (see black box). Other search engines are available to search the web (Bing, Yahoo, DuckDuckGo), each of which has its own index and algorithms to sort results by relevance.

GUI (graphical user interface): see User interface

Hard Disk Drive (hard drive): A magnetic data storage device that uses rapidly rotating disks (platters) coated with magnetic material paired with magnetic heads that read and write data to the disks. Hard disks are the major form of storage in personal computers and servers, although solid state memory is becoming more widely used. Hard drives have a lifespan of 3-5 years.

Hosting; see Web Hosting

HTML (HyperText Markup Language): A markup language that uses tags to describe the structure of what something will look like online, and specifying the format of text (font, bold, italics), the header of a page, etc. HTML is now commonly used in conjunction with CSS, another markup language that modifies the design and appearance of HTML elements and offers an easier way of creating the style of a site.

HTTP (Hypertext Transfer Protocol): The system of rules used to communicate data in the web; it appears as the first part of a URL or web address. HTTP requests are sent by clients such as web browsers to servers, which return responses. If the URL is valid and the connection is established, the server sends a webpage and related files or other content. HTTPS is an extension of HTTP that uses an encrypted protocol to provide secure communication.

Image Search: A text search for of an index of images that returns a list of image files identified based on keywords and metadata such as title and caption associated with image files. Algorithms rank image search results for relevance based on that textual information. Image search does not search the image files themselves. You can search image files using Reverse Image Search, but only for images that match an image you provide.

Interface: see User interface

Internet (interconnected network): A global system of interconnected computer networks – a network of networks – that use a variety of different telecommunications technologies (DSL, TV cable, fiber optics) and relay information using the Internet Protocol (IP). The large number of redundant network links and the lack of central control make the internet very resilient. Services delivered on the internet include the Web, social media, and email.

IP address (internet protocol address): A unique numerical label assigned to devices connected to the internet. An IP address is used to identify a device, and where it is in a network, which allows a path to the machine to be established. Most users do not use IP addresses to access the web; instead they use a more easily remembered domain name, which a DNS (domain name server) translates into an IP address

. ISP (internet service provider): An organization that provides access to the internet and other related services such as hosting. ISPs can connect to the network and transmit data using different technologies, including copper wire telephone lines, television cable, and fiber optic cable. Tier 1 ISPs operate the global internet backbone. Other ISPs buy access to the internet from Tier 1 ISPs and sell it to users. In 2019, just over half of internet access in the US was provided by cable TV providers, and most of the remainder by telephone companies.

JPEG: An image format that uses lossy compression – which compresses images by discarding some data when they are edited and saved. The most commonly used format in digital cameras and for storing and transmitting image files online. See also TIFF; Pixel; Resolution.

KML (Keyhole Markup Language); KMZ file: An XML-based markup language that uses tags to describe geographic information about a place that can be displayed on maps. Originally developed for Google Earth. KMZ files are compressed KML files.

LAMP (Linux, Apache, MySQL, PHP/Python): An open source software bundle that is used to create web sites and web applications: Linux is the operating system, Apache is the webserver, MySQL is the database, PHP/Python is the scripting language.

LMS (Learning Management System): A content management system designed for teaching and learning, offering the ability to organize content by classes and courses, design quizzes, and manage grades and monitor the activity of students. The best known example is Blackboard.

Lossless compression; see TIFF; GIF

Lossy compression; see JPEG

Machine Learning: Algorithms that automate analysis by taking a sample of training data and progressively building a statistical model to categorize or classify data. Commonly used when the features and patterns of the data are too fuzzy to make it feasible to use strict instructions to sort the data.

Markup language: A computer language that uses tags to define elements within a document. The language contains standard words rather than code so is human readable. The two most popular markup languages are HTML and XML. Historians and literary scholars often use an adaptation of XML called TEI to identify and mark up particular non-technical elements of a document (e.g. people or places). See also KML.

Metadata: Data about data, or information that describes an item. Metadata is what you read in library catalog records or museum collections management systems. Standardized metadata uses agreed-on spelling, language, date formats etc in order to allow metadata to be compared. Metadata standards or schemas are sets of structured and standardized metadata, developed to describe resources for a particular purpose or community. Dublin Core is a widely used metadata standard for describing digital and physical resources.

Modem: A device that provides a connection to the internet, and encodes data for transmission. over networks of telephone wire, television cable or fiber optic cable and decodes transmitted data. Most home modems are now combined with a router to allow devices to establish a connection to the internet via wi-fi rather than by using Ethernet cables plugged into the modem.