Translation look aside table
  Speed of access is critical in virtual memory.

  TLB is a small block of associative cache.

  It holds a two part list
    The most recently used virtual page ids.

    And the frames they are stored in.

  Even if all physical memory frames are in use,
    Because of locality, only a small number of frames will probably 
    be accessed during a given period of time. 

  Virtual page ids stored in random order and searched in parallel.

  The memory management unit checks for a page match in cache

  If found, 
    It uses the cached information

  Else 
    It will access the full page table (found in main memory).