What is the purpose and main areas of application of Redis in modern programming?

Redis is a high-performance in-memory data store supporting various data structures (strings, lists, sets, hashes, etc.). Its main purpose is fast caching, session storage, queue and counter implementation.

Main areas of Redis application:

• Caching: reducing load on the database and speeding up access to frequently used data.
• Session storage: in web applications to save user state.
• Message queues: using data structures like lists to implement task queues.
• Counters and ratings: using atomic operations.
• Pub/Sub systems: for message exchange between application components.

Example of using Redis in Node.js for data caching:

const redis = require('redis');
const client = redis.createClient();

client.on('error', (err) => console.log('Redis Client Error', err));

async function cacheData(key, value) {
  await client.connect();
  await client.set(key, JSON.stringify(value), { EX: 3600 }); // cache for 1 hour
  await client.disconnect();
}

cacheData('user:123', { name: 'Ivan', age: 30 });