U2400U243F

U+2400 to U+243F, known as the Control Pictures block, is a range in the Unicode Standard that provides graphical symbols for C0 control codes. The block comprises 64 code points, each mapping to a visual representation of a control character that would otherwise be non-printing in ordinary text. It was designed to aid debugging, documentation, font testing, and data inspection in environments where control characters must be observed.

The symbols in this block range from U+2400 SYMBOL FOR NULL to higher codes that represent other control functions, such as START OF HEADING, LINE FEED, CARRIAGE RETURN, and SHIFT OUT/IN, among others. The intended use is to give developers and editors a visible proxy for non-printing characters, helping to diagnose formatting or transmission issues without altering the underlying data.

Rendering of these glyphs depends on font and rendering support. Some fonts provide complete glyph coverage for the entire range, while others may display missing glyphs as empty boxes or fall back to alternate symbols. Importantly, these pictures are representations of control codes and do not change their semantic meaning in text processing.

In practice, the Control Pictures block is primarily employed in software development, debugging, documentation, and testing scenarios where it is advantageous to visualize control characters. It is one of several Unicode blocks designed to make non-printing characters observable in a portable, human-readable form.