We are running out of space. Not physical space, but digital space. We are currently living in the "Zettabyte Era." Every day, humanity generates approximately 328.77 million terabytes of data. By 2025, the global "datasphere" is expected to reach 175 zettabytes. From 4K videos, scientific datasets, and autonomous vehicle logs to the massive training models for Generative AI (like BharatGPT), our hunger for data is wildly outpacing our ability to store it. We are generating data faster than we can manufacture the hard drives to hold it. Traditional silicon-based storage (SSDs, HDDs) and magnetic tapes are hitting physical limits in terms of density and durability. They are fragile, temporary, and resource-heavy. Data centers are becoming massive energy drains, competing with entire cities for power grids. But nature solved this problem billions of years ago. Evolution has already perfected the ultimate storage medium: a microscopic, ultra-dense, and energy-neutral ...

Multinational companies (MNCs) like Google, Amazon, Netflix, and Microsoft focus less on syntax trivia and more on scalability, system design, and deep internal knowledge of the runtime. This guide covers the most high-impact topics. Part 1: Core JavaScript Deep Dives Focus: How the language actually works under the hood. 1. Explain the Event Loop in detail. How do microtasks differ from macrotasks? Answer: The Event Loop is the mechanism that allows Node.js to perform non-blocking I/O operations despite being single-threaded. It offloads operations to the system kernel whenever possible. Call Stack: Executes synchronous code. Macrotasks (Task Queue): setTimeout , setInterval , setImmediate , I/O callbacks. Microtasks (Microtask Queue): Promise callbacks ( .then / .catch ), process.nextTick . Critical Distinction: The Event Loop checks the Microtask Queue after every completed task in the Call Stack and before moving to the next Macrotask. This means process.nextTick and Prom...