API Connectivity Overview

Aug 25, 2025

Overview

This lecture explains how Application Programming Interfaces (APIs) enable seamless connectivity between devices, applications, and databases, allowing real-time data exchange and interaction across the digital world.

What is Connectivity?

  • Connectivity allows instant interaction and access to global resources from any device.
  • It enables tasks such as making purchases, bookings, and reservations online.

Understanding APIs

  • An Application Programming Interface (API) is a set of routines, protocols, and tools in software development.
  • APIs specify operations, required inputs, expected outputs, and data types for software components.
  • APIs act as messengers, processing requests and delivering responses between different systems.

API Analogy: The Waiter Example

  • An API functions like a restaurant waiter who takes your order, communicates with the kitchen, and delivers your food.
  • The waiter (API) links the customer (user) and kitchen (system), passing requests and responses.

Real-World API Example: Online Flight Booking

  • When booking flights via an online travel service, the service uses the airline’s API to access seat availability and prices.
  • APIs enable third-party services to communicate with different airline systems, collect data, and present information to users.
  • APIs handle additional requests such as meal preferences and baggage options.

Role of APIs in Daily Interactions

  • APIs are essential for any interaction involving data and devices, such as travel bookings or financial transactions.
  • They create the connectivity that powers the digital world by enabling application and device interoperability.

Key Terms & Definitions

  • API (Application Programming Interface) — A set of rules and tools that allow different software components to communicate and share data.
  • Connectivity — The ability of devices and applications to communicate and exchange data in real time.

Action Items / Next Steps

  • Review examples of APIs used in everyday web and mobile applications.
  • Prepare questions about API roles for next class discussion.