Braille has been extended to an 8 dot code, particularly for use with braille embossers and refreshable braille displays. In 8 dot braille the added dots are added at the bottom of the cell, giving a cell 4 dots high by 2 dots wide. The additional dots are called 7 (for the lower-left dot) and 8 (for the lower-right dot). 8-dot braille has the advantages that capital and lower cases of the letters are directly coded in the cell, a capital letter does not need two cells. All the printable ASCII characters can be represented in a single cell, and all 256 possible combinations of 8 bits are encoded by the Unicode standard. Braille with six dots is frequently stored as braille ASCII.