U+FEFF "" Zero Width No-Break Space Unicode Character

U+FEFF "" Zero Width No-Break Space is an invisible, nonprinting code point that serves two distinct essential roles depending on context. Primarily, it functions as a Byte Order Mark or BOM, placed at the very beginning of a text file or data stream to indicate the byte order and encoding scheme, most commonly for UTF-16 and UTF-32 text. Additionally, it acts as a legitimate zero width no-break space within text content, preventing line breaks between adjacent characters without adding any visible whitespace, though its use for this purpose has been largely deprecated in favor of the separate character U+2060 Word Joiner.