2.a Clients

• Definition: A client is any entity that initiates a request to a server. It's the "requester" in a client-server architecture.
• Types of Clients:
  • Web Browsers: The most common type of client. They request web pages, images, and other resources from web servers using HTTP/HTTPS.
  • Mobile Apps: Native apps on smartphones and tablets that communicate with servers to retrieve and send data. They often use APIs (Application Programming Interfaces) to interact with servers.
  • Desktop Applications: Software applications that run on a user's computer (e.g., email clients, games). They may connect to servers for updates, data synchronization, or other services.
  • Other Services (Microservices): In a microservices architecture, one service can act as a client to another service. This is very common in modern distributed systems.
  • IoT Devices: Internet of Things devices (e.g., smart thermostats, sensors) can also act as clients, sending data to and receiving commands from servers.
• Key Considerations:
  • Client-Side Logic: Clients often have some level of logic (e.g., JavaScript in a web browser, code in a mobile app) to handle user interaction, data processing, and presentation.
  • Communication Protocols: Clients use various protocols to communicate with servers (e.g., HTTP, HTTPS, WebSockets, gRPC).
  • State Management: Clients may need to manage their own state (e.g., user session information, cached data).
• Example When you type "www.google.com" into your web browser and press Enter, your browser (the client) sends a request to Google's servers.