Material UI (MUI)

MUI Core (v6) is the gold standard for React UI. v6 introduces Pigment CSS (Zero-runtime CSS-in-JS) for compatibility with React Server Components (Next.js App Router).

When to Use

• Enterprise: Consistent, rigorous design system.
• Complex Data: MUI X (DataGrid) is the most powerful table library for React.
• Accessibility: First-class a11y support.

Core Concepts

The sx prop

Superset of CSS. sx={{ mt: 2, color: 'primary.main' }}.

Theme Provider

Global design tokens (palette, typography, breakpoints).

Slots / SlotProps

Deep customization of internal sub-components.

Best Practices (2025)

Do:

• Use Pigment CSS: For RSC compatibility.
• Use Box: Instead of div for layout.
• Use MUI X: For Data Grids and Date Pickers.

Don't:

• Don't use makeStyles: It is deprecated. Use styled() or sx.

References

• Material UI Documentation