What role do placeholders play within a block?

Placeholders within a block serve an important purpose by reserving spaces for content that will be added later. This flexibility allows developers to create a structured design where specific areas are designated for dynamic content elements, such as text, images, buttons, or even other blocks. Developers can design the layout without needing to finalize the content immediately, which streamlines the development process and helps in managing UI consistency.

This ability to reserve spaces for future content is especially useful in responsive design, where the types and amounts of information displayed may vary based on user interactions, permissions, or data availability. Thus, using placeholders helps in organizing the layout and maintaining a clear structure throughout the application development process.