The “law of common region” is a principle in visual perception and design that can be applied to user experience (UX) design. This principle, which is often attributed to the field of Gestalt psychology, suggests that elements placed within a common region or boundary are perceived as a group or related to each other, even if they have individual differences or characteristics.

In UX design, the law of common region can be leveraged to enhance the organization and understanding of information on a user interface. Here are some ways in which this principle can be applied:
- Grouping Related Elements: Elements that are related, such as buttons, labels, and input fields within a form, should be placed within a common region or container. This creates a visual association between them, making it clear to users that they are part of the same task or form.
- Menu Navigation: In navigation menus, grouping related items together under clear headings or sections (common regions) helps users quickly understand the structure of the content. For example, grouping menu items for “Home,” “About Us,” and “Contact” under a common header like “Main Menu” creates a logical grouping.
- Card-Based Layouts: Card-based layouts, often used in mobile app design and responsive web design, make effective use of the law of common region. Each card acts as a common region, containing related content such as images, text, and actions.
- Data Tables: In data-heavy interfaces, organizing information into rows and columns creates common regions. Users can easily identify relationships between data points within the same row or column.
- Tabs and Accordion Menus: Tabs and accordion menus create distinct common regions for organizing and presenting content. Users understand that the content within each tab or accordion panel is related and can switch between them to access different information.
- Form Validation: When displaying validation messages for input fields, place the error message within the same common region as the associated input field. This makes it clear which input field the error message pertains to.
- Visual Hierarchy: Apply the law of common region to establish a clear visual hierarchy on a webpage or app screen. Use common regions to group content by importance or relevance, with the most important elements receiving more prominent placement.
- Whitespace and Separators: Effective use of whitespace and visual separators can create common regions and help differentiate sections of a page or screen.
By leveraging the law of common region in UX design, you can improve the user’s ability to understand and navigate the interface. It helps users quickly grasp the relationships between elements and enhances the overall user experience by reducing cognitive load and improving information organization.