CS 146: Introduction to Web Programming and Project Development

Vocabulary practice flashcards covering web development fundamentals, networking protocols, HTML semantics, CSS selectors and layouts, JavaScript core concepts, software engineering principles, and multimedia formats.

Circuit Switched Network

An early networking model where communication lines were physically connected by switchboard operators to complete a dedicated electrical circuit, resulting in inefficient bandwidth usage and poor scalability.

Packet Switched Network

A network architecture where messages are broken into discrete, numbered packets that travel across diverse routes without requiring a continuous physical connection, officially unified across ARPANET via TCP/IP on January 1, 1983.

Tier 1 Network

High-speed fiber optic backbone networks that route global Internet traffic and peer directly with all other Tier 1 networks across the globe without paying transit fees.

Port Address Translation (PAT)

A networking technique that enables multiple devices on unrelated private networks to share a single public IPv4 address, mitigating IPv4 address exhaustion after its depletion in 2011.

User Datagram Protocol (UDP)

A connectionless transport layer protocol that transmits packets without acknowledgment or retransmission guarantees, preferred in time-sensitive applications such as VoIP, online gaming, DNS lookups, and live video streaming.

Domain Name System (DNS)

A scalable, distributed naming system that translates human-readable domain names into numerical IP addresses through a hierarchical lookup process involving Root Name Servers, TLD Name Servers, and Authoritative DNS Servers.

Uniform Resource Locator (URL)

A standardized string that uniquely identifies a web resource, composed minimally of a protocol and a domain name, and optionally containing a port, path, query string, and fragment identifier.

Cumulative Layout Shift (CLS)

A user-centric browser rendering performance metric that measures visual stability by tracking the extent and frequency of unexpected layout shifts that occur as web assets download and render.

LAMP Stack

A traditional open-source web application software bundle consisting of the Linux operating system, Apache web server, MySQL relational database management system, and PHP scripting language.

Document Object Model (DOM)

A hierarchical tree representation created internally by web browsers to model HTML document structures, defining familial ancestor, parent, child, descendant, and sibling relationships between elements.

Semantic Markup

The practice of authoring HTML using tags that convey the meaning and structure of the document rather than its visual presentation, enhancing maintainability, accessibility, performance, and search engine optimization (SEO).

Character Entity

A specific code format beginning with an ampersand and ending with a semicolon used in HTML to render reserved syntax characters or special symbols, such as < for '<' or © for '©'.

CSS Rule

The core building block of a cascading style sheet, consisting of a selector identifying target HTML elements followed by a declaration block enclosed in curly braces that contains property-value pairs.

CSS Specificity

The weighting system used by browsers to resolve conflicting style rules, calculated using four tiers: inline styles ($1000$), ID selectors ($0100$), class/attribute/pseudo-class selectors ($0010$), and element/pseudo-element selectors ($0001$).

Collapsing Margins

A CSS rendering behavior where adjoining vertical margins of adjacent or nested block elements combine into a single margin equal to the maximum margin value, while horizontal margins never collapse.

rem (Root EM)

A relative CSS measurement unit equal to the computed font size of the root document element (<html>), avoiding compound calculation issues associated with standard nested em units.

CSS Variables

Custom CSS properties defined with a double-hyphen prefix (e.g., --bg-color-main) typically within the :root selector and referenced via the var() function to centralize shared styles.

border-collapse

A CSS table property that selects the border model; setting it to 'collapse' forces adjoining table data and header cells to share a single border rather than maintaining separated independent borders.

HTTP GET Method

An idempotent HTTP request method that requests a specified resource and transmits form parameters visibly as key-value pairs appended to the URL query string, caching inputs in browser history.

HTTP POST Method

An HTTP request method commonly used with HTML forms that packages submitted data inside the request payload body rather than the URL, allowing binary data uploads and hiding data from browser history and URL bars.

Fieldset and Legend

Semantic HTML form elements where <fieldset> groups logically related input controls together and <legend> defines a visible caption describing that grouped container.

Absolute Positioning

A CSS layout scheme (position: absolute) that removes an element from the normal document flow and positions it relative to its closest positioned ancestor or the initial containing block.

Flexbox Architecture

A one-dimensional CSS layout model consisting of a flex container and flex items, organized along a primary main axis and an orthogonal cross axis to distribute space and align content dynamically.

Fraction Unit (fr)

A flexible CSS Grid length unit representing a proportional fraction of the available free space within a grid container.

Viewport Meta Tag

An HTML header instruction (<meta name="viewport" content="width=device-width, initial-scale=1" />) that forces mobile browser rendering viewports to match device pixel widths without scaling out.

Sass Mixin

A CSS preprocessor structure defined using @mixin and invoked via @include that packages groups of CSS declarations into a reusable component to eliminate repetitive styling rules.

Dynamic Typing

A programming language feature of JavaScript where variables are not bound to a fixed data type at declaration and can hold different data types interchangeably at runtime.

Callback Function

A function supplied as an argument to another function, which is subsequently invoked within the receiving function to complete an action, perform an calculation, or handle an asynchronous response.

Closure (JavaScript)

A function packaged with references to its surrounding lexical scope environment, allowing the inner function to retain access to variables declared in its outer scope even after the outer function has completed execution.

Arrow Function Syntax

A compact ES6 function expression syntax (param => expression) that does not create its own 'this' binding, inheriting 'this' context directly from its enclosing lexical parent scope.

Project (PMI Definition)

A temporary endeavor undertaken to create a unique product or service, characterized by a distinct purpose, cross-functional resource requirements, customer sponsorship, and inherent uncertainty.

Waterfall Model

A linear-sequential software development lifecycle process where project activities cascade through discrete phases (Requirements, Design, Implementation, Testing, Deployment, Maintenance) without phase overlap.

Agile Methodology

An iterative project management and software development methodology that delivers software incrementally in short cycles ($1$ to $3$ weeks), emphasizing cross-functional collaboration and adaptability to evolving customer needs.

Joint Application Design (JAD)

An intensive requirements-gathering workshop technique where business users, IT specialists, and management collaborate in structured sessions to define and validate system requirements.

Definition of Done (DoD)

A formal, agreed-upon checklist established by project stakeholders verifying that a feature or user story is completely coded, tested, documented, and approved before being marked as finished.

Encapsulation

An object-oriented design principle of packaging related fields and operations within a single unit and restricting direct external modification by keeping properties private and providing public accessor methods.

Inheritance (OOP)

An object-oriented programming relationship where a derived subclass inherits methods and attributes from a generalized superclass, avoiding code duplication and enabling specialization.

Polymorphism

The object-oriented capability of an entity to take on multiple forms, enabling a parent class or interface variable reference to execute overridden methods on diverse child class instances.

Pesticide Paradox

A core software testing principle stating that executing the exact same set of test cases repeatedly will eventually cease uncovering new bugs, necessitating continuous updates and additions to the test suite.

Raster Image

A bitmap graphic consisting of a rectangular grid of individual colored square pixels whose resolution is fixed, resulting in visible pixelation and quality degradation when enlarged.

Vector Image

A resolution-independent digital image format composed of mathematical primitives such as lines, curves, and polygons that can be scaled infinitely without any loss of visual crispness or quality.

CMYK Color Model

A subtractive color model based on cyan, magenta, yellow, and key (black) inks used in physical printing, where overlapping pigment dots absorb wavelengths of light to produce colors.

GIF Run-Length Compression

A lossless compression algorithm (LZW) used by 8-bit indexed GIF files that reduces file size by storing continuous horizontal runs of identical color pixel values as count-color pairs.

Codec vs. Container

In digital media, a codec is the compression/decompression algorithm used to encode raw audio or video data (e.g., H.264, VP8, AAC), whereas a container format (e.g., MP4, WebM) packages multiple synchronized streams and metadata into a single file.