Fixed and variable bit widths
		¡ To encode English text, we need 26 lower case letters, 26 upper case letters, and a handful of punctuation ¡ We can get by with 64 characters (6 bits) in all ¡ Each character is therefore 6 bits wide ¡ We can do better, provided: l Some characters are more frequent than others l Characters may be different bit widths, so that for example, e use only one or two bits, while x uses several l We have a way of decoding the bit stream ¡ Must tell where each character begins and ends