Technology

Interchangeable parts: standardization, history, and industrial impact Interchangeable parts Interchangeable parts are uniform components made to tight tolerances so they can be mass-produced, assembled, repaired, and replaced easily. This article explains principles, hist…

Interface (User Interface and Shell): Types, History, and Uses Interface Overview of user interfaces and shells: what they are, main types (CLI, GUI, touch, voice), history, components, common uses, and distinctions such as UI vs API and accessibility.

Interferometer: principles, types, and applications Interferometer Instrument that splits and recombines waves to measure phase, distance, and spectral properties; central to optics, metrology, astronomy and gravitational-wave detection.

Interlaced video: technique, history, uses, and challenges Interlaced video Interlaced video is a scanning method that presents each picture as two interleaved fields to reduce flicker and conserve bandwidth; once dominant in broadcast TV, it now coexists…

International Data Encryption Algorithm (IDEA) International Data Encryption Algorithm Overview of the International Data Encryption Algorithm (IDEA): design, operation, history, security considerations, and practical use including PGP and licensing.

International Standard Book Number (ISBN) International Standard Book Number The ISBN is a standardized numeric identifier for books and related products, used worldwide for ordering, cataloguing, sales and rights management. It exists in 10- and 13-digit f…

International Standard Name Identifier (ISNI) International Standard Name Identifier ISNI is a 16-digit identifier that uniquely distinguishes contributors to creative works. Managed by the ISNI Agency and standardized by ISO, it supports cataloging, metadata linki…

Interrupt (computer systems) Interrupt An interrupt is a signal that temporarily halts normal program flow so a processor can respond to an external or internal event. Covers types, operation, history, uses, and key dis…

Interrupt latency in real-time and general-purpose systems Interrupt latency Interrupt latency is the delay between a hardware interrupt and the start of service. This article explains its causes, measurement, relevance to real-time systems, mitigation tech…

Invention: Definition, History, Types and Importance Invention A concise encyclopedia article on inventions: what they are, how they develop, notable types and examples, the role of inventors and patents, and distinctions between ideas and tan…

Inventor: creator of new devices, methods, and technologies Inventor An inventor devises new devices, methods or processes. This article explains what inventors do, types of inventions, historical development, examples, and legal and practical disti…

Inverter: Device that Converts Direct Current to Alternating Current Inverter An inverter converts DC electricity (from batteries or solar panels) into AC power used by household and industrial equipment. This article explains how inverters work, their histo…

Ion thruster: electric propulsion for spacecraft Ion thruster An ion thruster is a form of electric propulsion that accelerates charged particles to produce thrust. It provides low continuous thrust with high fuel efficiency, making it useful…

iOS — Apple's mobile operating system iOS iOS is Apple's proprietary mobile operating system for iPhone and similar devices. This article explains its design, history, device variants, development ecosystem, and security m…

iOS 10 — overview, features, history and device support iOS 10 iOS 10 is Apple’s 2016 major update to its mobile operating system. It introduced redesigned notifications and lock screen, expanded Siri and Messages capabilities, and changed sup…

iOS 11: features, history, reception, and impact iOS 11 Overview of iOS 11, Apple’s 2017 major iOS release: key features, iPad additions, compatibility changes, reception, adoption rates, and its place in Apple’s software evolution.

iOS 12 — Apple's twelfth-generation mobile operating system iOS 12 iOS 12 is the twelfth major release of Apple's iPhone and iPad operating system, emphasizing performance, stability, new privacy and productivity features, and developer tools for…

iOS 4 — Apple’s 2010 mobile operating system update iOS 4 Major 2010 release of Apple’s mobile OS that introduced multitasking, folders and developer APIs; rebranded iPhone OS to iOS and later unified iPhone and iPad with iOS 4.2.1.

iOS 5 — Apple's fifth major mobile operating system release iOS 5 iOS 5 is Apple’s fifth major iOS release, introducing Notification Center, iMessage, iCloud integration, and over‑the‑air setup and updates. It launched in 2011 and was succeeded b…

iOS 6 — Apple's sixth major mobile operating system (2012) iOS 6 iOS 6 is the sixth major release of Apple's mobile operating system, introduced in 2012. It added Apple Maps, Passbook, Facebook integration and other features; its final update wa…

iOS 7 — Major redesign of Apple's mobile operating system iOS 7 iOS 7 is the seventh major release of Apple's mobile OS, introduced in 2013. It brought a comprehensive visual redesign and new system features such as Control Center, improved mul…

iOS 8 — Apple's eighth major iOS release (2014) iOS 8 iOS 8, announced at WWDC 2014, brought HealthKit, HomeKit, Metal, app extensions, Touch ID for third-party apps, Continuity features and third‑party keyboards; public release on Se…

iOS 9 (Monarch): Apple's 2015 mobile operating system iOS 9 iOS 9 is Apple's 2015 release for iPhone and iPad, focusing on performance, battery life and productivity with a News app, richer Notes, improved Maps, Proactive Siri/Spotlight and…

iPad: Apple's Line of Multi‑Touch Tablet Computers iPad Overview of the iPad family: design, hardware and software characteristics, development history, common uses, and how it differs from laptops and earlier tablets.

iPad (1st generation) Apple's original iPad, released in 2010, introduced a 9.7-inch multitouch tablet with the Apple A4 chip, iPhone OS 3.2 and models with Wi‑Fi or Wi‑Fi + 3G, helping establish the mo…

iPad (3rd generation) The third-generation iPad, marketed as “The new iPad” and often called iPad 3, is Apple’s 2012 tablet that introduced a Retina display, an A5X chip, improved camera and North Ameri…

iPad (4th generation) — iPad with Retina display iPad (4th generation) Fourth-generation iPad by Apple, marketed as iPad with Retina display; introduced in 2012 with the A6X chip and Lightning connector. Retained Retina screen and received subsequent…

iPad Air (first generation): overview, design, and legacy iPad Air A compact, lighter 9.7-inch iPad introduced by Apple in 2013. Covers design, hardware, software updates, uses, and how it differs from other iPads.

iPad Air 2: overview, design, hardware and legacy iPad Air 2 Second-generation 9.7-inch iPad introduced by Apple in October 2014. Thinner design, Touch ID, improved performance and a laminated anti-reflective display; notable for its influen…

iPad Mini — Apple's compact tablet line iPad Mini A concise encyclopedia entry on the iPad Mini, Apple’s smaller iPad series: design, history, typical features, uses, and how it differs from full‑size iPads.

iPad mini (1st generation) — compact tablet introduced in 2012 iPad Mini (1st generation) Overview, design, hardware, software, release and legacy of Apple’s first iPad mini (7.9-inch) introduced November 2012, a smaller alternative to the standard iPad line.

iPad mini (5th generation) Compact tablet from Apple released March 18, 2019. Updated internals, Apple Pencil support, A12 Bionic chip, and options for 64GB or 256GB storage with Wi‑Fi or cellular models.

iPad Mini 2 (iPad mini with Retina display) iPad Mini 2 Apple's second-generation 7.9-inch tablet, released in 2013. Introduced a 2048×1536 Retina display and A7/M7 processors, shared internals with the iPad Air, and was succeeded by th…

iPad mini 3 Apple’s third-generation 7.9-inch iPad mini, released in 2014. An incremental update introducing Touch ID and a Gold finish, otherwise sharing much of its hardware with the iPad mi…

iPadOS: Apple’s Tablet Operating System iPadOS iPadOS is Apple’s operating system tailored for iPad, emphasizing multitasking, Apple Pencil support, desktop-class browsing, and features that leverage larger displays for product…

iPhone (Apple smartphone series) iPhone A line of smartphones by Apple introduced in 2007 that combined touch-driven interfaces, mobile computing, multimedia and an app ecosystem centered on iOS and the App Store.

iPhone 11 Apple's iPhone 11 (2019) is a 6.1-inch smartphone with dual rear cameras, the A13 Bionic chip, multiple color and storage options, and iOS features; marketed as the lower-cost mode…

iPhone 11 Pro Apple's 2019 high-end iPhone with a triple rear camera, Super Retina XDR OLED display, A13 Bionic chip, enhanced battery life, and new midnight green finish. Shipped with an 18W US…

iPhone 3GS (Apple smartphone, 2009) iPhone 3GS Third-generation iPhone introduced by Apple in 2009. The 3GS emphasized improved speed, a better camera with video, and new software features while retaining the iPhone 3G design.

iPhone 4: design, features, controversy and legacy iPhone 4 The iPhone 4 is Apple's 2010 smartphone notable for its Retina display, front-facing camera and new glass-and-steel design; it introduced FaceTime and drew attention for an antenna…

iPhone 4S Apple's iPhone 4S (released 2011) refined the iPhone 4 design with upgraded internals, iOS 5 features, an improved camera and the introduction of the Siri voice assistant.

iPhone 5 — Apple’s 2012 sixth-generation smartphone iPhone 5 The iPhone 5, introduced by Apple in September 2012, is the sixth-generation iPhone featuring a 4-inch Retina display, Lightning connector, LTE support and a thinner aluminum desig…

iPhone 5C — design, features, history, and legacy iPhone 5C Apple's 2013 colorful smartphone that used a polycarbonate shell and iPhone 5-class hardware. Positioned as a lower-cost alternative to the 5S, it shipped with iOS 7 and received l…

iPhone 5S — Apple smartphone introduced in 2013 iPhone 5S The iPhone 5S is a 2013 Apple smartphone that retained the iPhone 5 exterior while adding a 64-bit A7 processor, Touch ID fingerprint recognition, an improved camera with True Tone…

iPhone 6 — Apple's 2014 phones with larger displays iPhone 6 The iPhone 6 and 6 Plus are Apple's 2014 smartphones that introduced bigger displays, a thinner curved design, new A8 processor, Apple Pay support, and notable cultural and industr…

iPhone 6S The iPhone 6S and 6S Plus are Apple’s 2015 smartphones that introduced 3D Touch, Live Photos, a 12 MP rear camera and improved performance over the iPhone 6. Available in several f…

iPhone 7 Apple’s tenth-generation iPhone family introduced in 2016, notable for a new Home button, removal of the headphone jack, updated cameras and water resistance.

iPhone 8 (Apple smartphone) iPhone 8 Apple iPhone 8 and 8 Plus — 2017 models featuring glass backs, A11 Bionic processor, True Tone Retina HD displays, Qi wireless charging, improved cameras, Touch ID and iOS software…