The lowest layer is the "grid", basically a DHT (Distributed Hash Table)
which maps URIs to data. The URIs are relatively short ascii strings
-(currently about 140 bytes), and each is used as references to an immutable
+(currently about 140 bytes), and each is used as a reference to an immutable
arbitrary-length sequence of data bytes. This data is distributed around the
grid in a large number of nodes, such that a statistically unlikely number
of nodes would have to be unavailable for the data to become unavailable.