In Blender 3D modeling, .blend files are the native, core format that stores all project data, serving as the foundation for creating, saving, and managing 3D models.
They act as comprehensive containers, holding 3D models, textures, animations, and scene settings in one integrated file. This ensures all elements remain linked, allowing users to edit, adjust, or refine any part of the project without losing context or data.
Additionally, .blend files enable progress tracking—users can save work at any stage and revisit or modify projects later. They also facilitate collaboration, as sharing a single .blend file ensures others access the complete, editable project.
Overall, .blend files ensure seamless workflow continuity, making them indispensable for efficient 3D modeling in Blender.