Each 1 or 0 in a number takes 1 bit, so that 11011 is a 5-bit number. 8 bits make 1 byte. The maximum number of possible unique values in a string of digits is its base raised to the power of the number of digits. All numbers from 0 up to 255 can be stored using only one byte. All data and information in the computer are represented in this manner.
Characters use a character representation scheme to represent characters in binary form.
Everything in the computer is in 0s and 1s. These are converted to decimal and character format to make it easier for humans to understand. See the 'Character Representation' section in the menu at the top of the page.