What are Web Components? - Explanation & Meaning

Definition

Web Components are a set of web standards that allow developers to create reusable, encapsulated HTML elements that work in any web application regardless of the framework used.

Technical explanation

Web Components consist of three core specifications. Custom Elements allow developers to define new HTML tags with custom behavior via the customElements.define() API and the HTMLElement class. Shadow DOM provides DOM and CSS encapsulation by creating a separate DOM tree isolated from the main document, preventing styles from leaking and external styles from affecting the component. HTML Templates with <template> and <slot> elements define reusable markup structures that are only rendered when activated. Lifecycle callbacks (connectedCallback, disconnectedCallback, attributeChangedCallback) provide hooks for initialization, cleanup, and reacting to attribute changes. Declarative Shadow DOM enables server-side rendering of Web Components. Libraries like Lit and Stencil simplify writing Web Components with reactive properties, decorators, and TypeScript support. Web Components are fully interoperable with frameworks like React, Vue, and Angular, making them ideal for design systems shared across frameworks. Adoption continues to grow as all modern browsers fully support the specifications.

How MG Software applies this

MG Software uses Web Components when clients need components that work across multiple frameworks and projects. We build framework-agnostic UI components with Lit that are reused in both React and Vue projects. This reduces duplication and ensures consistency across the client's entire digital ecosystem.

Practical examples

• A large enterprise building a Web Component library with Lit used across their React marketing site, Vue customer portal, and vanilla JavaScript legacy application, ensuring consistent UI everywhere.
• An embedded customer review widget distributed as a Web Component, so any website can add the element with a simple <review-widget> tag without framework dependencies.
• A design system offering tokens and base components as Web Components with framework-specific wrappers for React and Angular that are automatically generated.

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