Chunking enhances working memory, not by increasing the number of items you can hold in working memory, but by increasing the size or complexity of those items.
    -- Example: The six letters "F D R J F K" may be chunked into "FDR and JFK"
    -- Note that this requires semantic organization of the material.

Do you remember your Social Security number.
It's "CHUNKed"
three digits-two digits-four digits