In Thin Provisioning, instead of provisioning the full storage space to the user, the software allocates disk space in a flexible manner based on the minimum space that is required by each user at the given time. In conventional storage (Thick Provisioning), the storage is allocated beyond the current requirements of application to accommodate any storage need in future. In this method, the space utilization rate is low and organizations pay for large amount of storage space but never use it completely.
With Thin Provisioning, the storage administrator allocates logical storage to an application. However, it is important to understand that at the given time, it is a mere logical space. The system releases the physical capacity only when the data is written. As soon as the defined threshold storage space limit is achieved, the application automatically provides the required additional storage to the user.