Self Reliant Initiatives Through Joint Action Interview Questions and Answers

Undefined means a variable has been declared but has not yet been assigned a value. Null is an assignment value that represents no value or no object.

• Undefined is a type in JavaScript that represents a variable that has not been assigned a value

• Null is a type in JavaScript that represents a deliberate non-value or no object

• Undefined is returned by functions that do not explicitly return a value

• Null is often used to indicate a deliberate non-value, such as when a variable is i...read more

JavaScript string methods are used to manipulate and work with strings.

• charAt() - returns the character at a specified index

• concat() - joins two or more strings

• indexOf() - returns the index of the first occurrence of a specified value

• replace() - replaces a specified value with another value in a string

• slice() - extracts a part of a string and returns a new string

• split() - splits a string into an array of substrings

• toLowerCase() - converts a string to lowercase letters

• toUpperC...read more

Types of inheritance include single, multiple, multilevel, hierarchical, hybrid, and multipath.

• Single inheritance involves a child class inheriting from a single parent class.

• Multiple inheritance involves a child class inheriting from multiple parent classes.

• Multilevel inheritance involves a child class inheriting from a parent class, which in turn inherits from another parent class.

• Hierarchical inheritance involves multiple child classes inheriting from a single parent class...read more

API methods are functions that allow software applications to interact with each other.

• GET - retrieves data from a server

• POST - sends data to a server to create a resource

• PUT - sends data to a server to update a resource

• DELETE - sends a request to a server to delete a resource

• PATCH - sends a request to a server to update a resource partially

Custom caching is the process of storing data in a cache that is specifically tailored to the needs of a particular application or system.

• Custom caching allows developers to control how data is stored, retrieved, and invalidated in the cache.

• Developers can define custom cache keys, expiration policies, and storage mechanisms based on the specific requirements of their application.

• Examples of custom caching include using in-memory caches like Redis or Memcached, implementing c...read more

Event emitters are objects in Node.js that allow for communication between different parts of a program by emitting named events.

• Event emitters are a core feature of Node.js for implementing the observer pattern.

• They allow one part of a program to signal that an event has occurred, and other parts to register to listen for that event.

• Listeners can be added to an event emitter using the 'on' method, and events can be emitted using the 'emit' method.

• Event emitters are commonly ...read more