Table of Contents

No.	Questions
1	Describe the architecture of a scalable Angular application you've built?
2	What is a prototype chain

1. Describe the architecture of a scalable Angular application you've built?

A scalable Angular app uses:

• Modular architecture with core, shared, feature, and lazy-loaded modules.

• Smart/dumb component separation (container vs presentational).

• State management with services or libraries like NgRx.

• Lazy loading to split bundles and reduce initial load time.

• Reusable UI libraries with shared components, directives, and pipes.

• Strict linting and TypeScript types to catch issues early.

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2. What is a prototype chain

   Prototype chaining is used to build new types of objects based on existing ones. It is similar to inheritance in a class based language. i.e, When you create an object using a constructor function or a class, the created object inherits properties from a prototype object.

   The prototype on object instance is available through Object.getPrototypeOf(object) or __proto__ property whereas prototype on constructor function is available through Object.prototype.

   

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3. What is closures

   A closure is a function that has been bundled together (enclosed) with references to its surroundings (the lexical environment). In other words, a closure allows an inner function to access the scope of an outside function. Closures are formed every time a function is created in JavaScript, during function creation time. An example of closures in Javascript is given below:

   function subtractor(subtractingInteger) {
   	return function(a) {
   		return a - subtractingInteger;
   	};
   }
   
   var subtract2 = subtractor(2);
   var subtract5 = subtractor(5);
   console.log(subtract2(5));  // 3 is logged
   console.log(subtract5(5)); // 0 is logged

   In this example, we have developed a function subtractor(subtractingInteger) that takes a single parameter subtractingInteger and returns a new function. Its return function accepts only one input, a, and returns the difference of a and subtractingInteger. The function 'subtractor' is essentially a function factory. It creates functions that have the ability to subtract a specified value from their arguments. The function factory creates two new functions in the example above: one that subtracts 2 from its argument and one that subtracts 5 from its arguments. Both subtract2 and subtract5 are closures. They have the same function body definition, but they hold lexical surroundings that are distinct. subtractingInteger is 2 in subtract2's lexical environment, but subtractingInteger is 5 in subtract5's lexical environment.

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🎯 Bonus Topics

• Event Emitters
• Worker Threads
• Child Processes
• Cluster Module
• WebSockets

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This README serves as a roadmap. Practice regularly and build small projects to reinforce concepts.

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Updated: April 2025