The "Resume" capability. These unique IDs allow the manager to track exactly which bits of data have been downloaded so that if your internet cuts out, you don't have to start the download from zero. 2. Software-Specific Content IDs

A "placeholder" file for data being streamed from a server.

Data Integrity. By assigning a unique hash like b8ee85f4... , the system can run a "checksum" to ensure the file you downloaded isn't corrupted or tampered with. If even one bit is wrong, the hash changes, and the system knows to redownload it.