What is the Translation Lookaside Buffer (TLB)

In a cached system, the base addresses of the last few referenced pages is maintained in registers known as the TLB that aids in faster lookup. TLB have those page-table entries that have been most recently used. Normally, every virtual memory reference causes 2 physical memory accesses- one to fetch appropriate page-table entry, and one to get the desired data. Using TLB in-among, this is reduced to just one physical memory access in cases of TLB-hit.