Web Development & Data Technologies Lecture

Vocabulary flashcards summarizing key web, mobile, XML, and DevOps concepts discussed in the lecture.

GET

Safe HTTP method used to retrieve data without altering server state.

POST

HTTP method that sends data to the server and can modify server state; not considered safe.

AJAX

Technique for asynchronous client-server communication that updates parts of a page without full reloads.

AJAX ReadyState 4 & Status 200

Indicates an XMLHttpRequest has completed successfully and its response can be processed.

XMLHttpRequest (XHR)

Browser API that enables AJAX calls to send/receive data asynchronously in the background.

setTimeout()

JavaScript timer function; unrelated to XMLHttpRequest operations.

MEAR

Stack combining MongoDB, Express, Angular, and React; incompatible because it mixes two frontend frameworks.

Express

Lightweight Node.js framework for building RESTful APIs and handling HTTP requests.

Node.js

JavaScript runtime for executing JS on the server side to build scalable back-end services.

Svelte

Front-end framework that compiles to vanilla JavaScript at build time and avoids a virtual DOM.

React

JavaScript library that builds component-based UIs using a virtual DOM for efficient updates.

Angular

TypeScript-based framework for building dynamic, component-driven web UIs.

Virtual DOM

In-memory representation of UI (used by React) to minimize direct DOM manipulation.

State Management

Technique for tracking and updating application data (e.g., user session, UI state) in front-end apps.

Lazy Loading

Performance tactic that defers loading of resources or components until they are needed.

Performance Optimization

Practices such as code splitting and lazy loading to improve app responsiveness and speed.

Extract, Transform, Load (ETL)

Data pipeline that extracts raw data, transforms it, and loads it into a target system.

Cloud → xlsx → Dashboard

Example of the Load phase in ETL where data is stored in a spreadsheet for reporting.

XML (eXtensible Markup Language)

Hierarchical markup language for structured data storage and transport.

Well-formed + Valid (XML)

XML must follow correct syntax (well-formed) and adhere to its DTD/XSD rules (valid).

DTD (Document Type Definition)

Schema that defines legal structure and elements of an XML document.

XSD (XML Schema Definition)

XML-based schema language with strict data typing, more powerful than DTD.

xs:sectional

Not a valid XSD data type; valid examples include xs:string, xs:int, xs:boolean.

XML Schema Declaration Syntax

defines an element and its data type in XSD.

XML DOM

Document Object Model that lets programs access and manipulate XML documents via methods like getElementsByTagName.

NodeList

Collection of DOM nodes returned after parsing XML; can be accessed by index.

XPath

Query language for selecting nodes in XML documents (e.g., /catalog/cd[1]/artist).

/catalog/cd[1]/artist

XPath expression that selects the element of the first in an XML document.

B. #PCDATA

Parsed Character Data in XML allowing text content inside elements to be processed by the parser.

Document Builder

Java utility that parses XML and builds a DOM structure programmatically.

JSON (JavaScript Object Notation)

Lightweight, semi-structured data format ideal for web APIs due to readability and compatibility.

Gson

Java library for converting JSON to Java objects and back using fromJson() and toJson().

Token-based Authentication

Security mechanism using JWTs to authorize API access and maintain session state.

Authentication

Process of verifying a user’s identity via credentials like tokens, passwords, or OAuth.

@react-native-firebase/app

React Native package that integrates Firebase; Flutter equivalent is firebase_core.

Firebase Cloud Messaging (FCM)

Service for sending push notifications to mobile apps built with Flutter or React Native.

Flutter

Cross-platform framework that compiles to near-native code for Android and iOS from a single codebase.

Flutter + Node.js + MongoDB

Valid full-stack combo where Flutter handles UI, Node/Express exposes APIs, and MongoDB stores data.

MongoDB

NoSQL document database often paired with Node.js for flexible JSON-like data storage.

Python

Readable, versatile programming language used in AI, web development, and scripting.

Java

Strongly-typed, object-oriented language widely used in enterprise and Android development.

C++

High-performance language favored for game engines and systems programming.

Microsoft C#

.NET language commonly used for Windows and enterprise applications.

Company (XML Element)

Child element of alongside title, artist, country, price in an XML catalog example.

B. 4 (XML children)

Each element contains four child tags such as

C. 5 (XML DTD example)

Illustrative DTD element containing five sub-elements: title, artist, country, company, price.

C. // DOM Access

Using DOM methods like getElementsByTagName()[0].textContent to retrieve XML data.

DevOps Stack: Git + CI/CD + Docker + AWS

Toolchain enabling version control, automated pipelines, containerization, and scalable cloud hosting.

Enterprise Backend Systems

Robust server architectures requiring core logic, security, and scalability for high-traffic apps.

Virtual DOM vs Real DOM

Virtual DOM batches updates and minimizes expensive direct manipulations of the real browser DOM.