"Shell and core" refers to a type of building construction where the basic structure is completed, but the interior finishes and systems are not. This approach allows tenants or buyers to customize the interior according to their needs. The "shell" includes the exterior walls, roof, and basic structural elements, while the "core" consists of essential services like elevators, stairwells, and restrooms. This method is commonly used in commercial real estate, particularly in office buildings. It provides flexibility for businesses to design their workspaces, making it an attractive option for companies looking to create a unique environment tailored to their operations.