Getting started with React

Before React

React is a library for building user interfaces from reusable components. Before starting, become comfortable with HTML, CSS and modern JavaScript. Arrays, objects, functions, imports and the difference between a value and a reference will appear throughout the work. A small project is a better introduction than a large collection of unfamiliar packages.

Begin with a small development project

A development tool such as Vite can create a working React project and a local development environment. Follow its current setup instructions and use a supported Node.js version. Locate the application entry point and the main component, then change a heading and inspect the result. Understanding where a page begins is more valuable than copying a complete application without knowing how its parts connect.

Components and JSX

A component is a function that describes a part of the interface. JSX lets that description resemble HTML while remaining part of JavaScript. Components can be composed: a page contains a header, a project list and individual cards. Keep each component focused on a clear responsibility. A component becomes useful when its purpose is understandable and it can be reused without depending on unrelated parts of the page.

Passing information with props

Props pass information from a parent component to a child. A project card can receive a title, description and image instead of embedding a particular project in its source. This separates the shape of the interface from the records it displays. Treat props as inputs. When something needs to change, the owning component should decide how that change is represented.

State and interaction

State represents information that changes while the user interacts with the page: the selected filter, the contents of a field or whether a panel is open. A state update asks React to produce the next interface. Use the appropriate setter rather than mutating an existing state object directly. The goal is a predictable relationship between the current data and what the visitor sees.

Lists, keys and conditions

Use an array to render repeated elements, such as project cards. Give each item a stable key drawn from its identity, especially when the list can be reordered or filtered. Conditional rendering shows the appropriate state: a result, an empty message or a loading indicator. Plan these states explicitly. A page should remain understandable when a list contains no items or a request fails.

Effects and outside systems

An effect connects a component to a system outside the rendering process, such as an event listener, a timer or a network request. Not every calculation needs an effect. Derive values from existing inputs when possible. When an effect creates a subscription or timer, provide the matching cleanup. This keeps the component’s behaviour predictable when it mounts, changes or leaves the page.

Practise with a complete small interface

A useful first exercise is a portfolio archive with a few records, category filters and an empty state. Add semantic headings and labels, test keyboard interaction and review the layout on a narrow screen. Organise the data and components so that adding another project does not require rewriting the interface. The habits learned in a small application scale better than a large amount of copied code.

Keep learning through concrete problems

React is one part of a web project. Browser behaviour, accessibility, performance and server responsibilities still matter. Read the current documentation when a concept is unclear and try a minimal example that isolates the question. Building a small feature, checking its behaviour and explaining the decision is a reliable way to develop confidence.