What is the difference between a web server and a web service?

A web server is a program that accepts HTTP/HTTPS requests from clients (browsers) and returns web pages, images, videos, and other files in response. A web service is a set of technologies for exchanging data between applications over a network. It does not necessarily return web pages and often uses formats like XML, JSON, or message passing (e.g., via SOAP, REST protocols).

// Example of a minimal web server in Node.js
const http = require('http');

const server = http.createServer((req, res) => {
  res.statusCode = 200;
  res.setHeader('Content-Type', 'text/plain');
  res.end('Hello World\n');
});

server.listen(3000, () => {
  console.log(`Server running at http://localhost:3000/`);
});

# Example of a simple web service (REST API) in Python using Flask
from flask import Flask, jsonify, request

app = Flask(__name__)

@app.route('/api/data', methods=['GET'])
def get_data():
    # Return data in JSON format
    return jsonify({'message': 'This is some data'})

if __name__ == '__main__':
    app.run(debug=True)

Characteristic	Web Server	Web Service
Main purpose	Servicing static and dynamic web pages for browsers	Providing programmatic functions for other applications
Data format	HTML, CSS, JavaScript, images, videos, etc.	XML, JSON, SOAP, messages, etc.
Protocols	Mainly HTTP/HTTPS	HTTP/HTTPS, SOAP, REST
Consumer	Web browsers (humans)	Applications, other web services (machines)
Connection with web service	Can run web services or host them	Can be part of or use a web server