Non Fixed-width ASCII
Most ASCII art is created using a monospace font, where all characters are identical in width (Courier is a popular monospace font). Early computers in use when ASCII art came into vogue had monospace fonts for screen and printer displays. Today most of the more commonly used fonts in word processors, web browsers and other programs are proportional fonts, such as Helvetica or Times Roman, where different widths are used for different characters. ASCII art drawn for a fixed width font will usually appear distorted, or even unrecognizable when displayed in a proportional font.
Some ASCII artists have produced art for display in proportional fonts. These ASCIIs, rather than using a purely shade-based correspondence, use characters for slopes and borders and use block shading. These ASCIIs generally offer greater precision and attention to detail than fixed-width ASCIIs for a lower character count, although they are not as universally accessible since they are usually relatively font-specific.
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