React vs Svelte: What are the differences?

# Introduction

1. **Virtual DOM**: React uses a virtual DOM to batch updates and minimize direct DOM manipulations, improving performance. Svelte, on the other hand, compiles components at build time to optimized vanilla JavaScript, eliminating the need for virtual DOM and resulting in smaller bundle sizes and faster initial load times.
2. **Reactivity**: React relies on state management and props to trigger re-renders, while Svelte automatically tracks reactive values and updates the DOM accordingly, simplifying the development process and reducing the need for additional state management libraries.
3. **Zero Runtime**: React requires the React library to be included in the final build, adding to the bundle size and potentially affecting performance. In comparison, Svelte compiles components into standalone JavaScript modules, resulting in zero runtime overhead and smaller bundle sizes.
4. **Code Structure**: React separates template logic and JavaScript code into JSX syntax, allowing developers to mix UI and logic. Svelte, on the other hand, combines markup, styles, and JavaScript into a single component file, making it easier to maintain and understand the codebase.
5. **Conditional Rendering**: React handles conditional rendering using JavaScript expressions within JSX, which can lead to complex and verbose code. In contrast, Svelte offers a simplified syntax for conditional rendering directly in the markup, improving readability and reducing boilerplate code.
6. **Component Lifecycle**: React components have lifecycle methods such as componentDidMount and componentDidUpdate to manage component state and effects. Svelte provides a more streamlined lifecycle approach, with lifecycle functions like onMount and onDestroy integrated directly into the component logic, simplifying component management and reducing code complexity.

In Summary, React and Svelte differ in their approach to virtual DOM, reactivity, runtime, code structure, conditional rendering, and component lifecycle, offering developers a choice between performance optimization, simplicity, and code maintainability.