0xD83C

0xD83C is the hexadecimal value of a high surrogate code unit in UTF-16 encoding. It is not a complete character on its own; rather, it forms the first half of a surrogate pair that encodes code points outside the Basic Multilingual Plane (BMP), specifically those above U+FFFF. In UTF-16, characters in the supplementary planes are represented by two 16-bit code units: a high surrogate in the range U+D800 to U+DBFF (such as 0xD83C) followed by a low surrogate in the range U+DC00 to U+DFFF (for example 0xDF0E). The resulting code point can be computed from both halves, and many common emoji and other symbols are encoded this way.

An illustrative example is the pair 0xD83C 0xDF0E, which encodes the Unicode code point U+1F30E, the Earth Globe Americas emoji 🌎. In UTF-8, the same character is represented by four bytes; surrogate pairs are a concept specific to UTF-16. When represented in escape sequences, such as in JSON or programming languages, you may see the literal sequence \uD83C\uDF0E.

Because surrogate pairs are two-code-unit sequences, malformed pairs (for example, a high surrogate not followed by a valid low surrogate) may produce invalid text or decoding errors. Proper handling requires correct decoding to obtain the intended code point.

Summary: 0xD83C is a high surrogate used in UTF-16 to encode many supplementary characters, most famously visible in emoji. It is not a standalone character.