There are different responsive layout techniques for creating adaptive designs based on screen size, including:
1. Using viewport meta tags and classes to detect screen widths starting at 320px for phones to 960px for tablets and desktops.
2. Implementing CSS media queries to load different style sheets based on max-width breakpoints like 480px, 720px, and 960px.
3. Integrating frameworks like Bootstrap which uses a mobile-first grid system and responsive CSS and JavaScript for cross-device compatibility.
4. Installing device detection plugins that recognize mobile browsers and redirect to a mobile-optimized theme.