Q31. What is a pure function?
A **pure function** is a function whose output depends only on its input arguments and produces no side effects. This means that given the same inputs, a pure function wi...
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Q32. How Virtual DOM works?
The _Virtual DOM_ works in five simple steps. **1. Initial Render** When a UI component renders for the first time, it returns JSX. React uses this structure to create a ...
Q33. What are the benefits of pure functions?
Some of the major benefits of pure functions are listed below, - **Easier testing:** Since output depends only on input, pure functions are simple to test. - **Predictabi...
Q34. What is the difference between Shadow DOM and Virtual DOM?
The _Shadow DOM_ is a browser technology designed primarily for scoping variables and CSS in _web components_. The _Virtual DOM_ is a concept implemented by libraries in ...
Q35. What is the purpose of the let keyword?
The `let` keyword in JavaScript is used to declare a **block-scoped local variable**. This means that variables declared with `let` are only accessible within the block, ...
Q36. What is React Fiber?
**React Fiber** is the **new reconciliation engine** in React, introduced in React 16. It’s a complete rewrite of React’s core algorithm(old stack-based algorithm) for re...
Q37. What is the difference between let and var?
You can list out the differences in a tabular format | var | let | | -------------------------------------------------------------- | ------------------------------------...
Q38. What is the main goal of React Fiber?
The goal of _React Fiber_ is to increase its suitability for areas like animation, layout, and gestures. Its headline feature is **incremental rendering**: the ability to...
Q39. What is the reason to choose the name let as a keyword?
The keyword `let` was chosen because it originates from mathematical notation, where "let" is used to introduce new variables (for example, "let x = 5"). This term was ad...
Q40. What are controlled components?
A **controlled component** is a React component that **fully manages the form element's state**(e.g, elements like ``, ``, or ``)) using React's internal state mechanism....