0x0D0A

0x0D0A is the two-byte hexadecimal sequence consisting of 0x0D (carriage return, CR) followed by 0x0A (line feed, LF). When interpreted as a single newline marker, this CRLF sequence is widely used in computing to terminate lines of text. The CR character moves the cursor to the start of the line, while LF advances to the next line, a convention that originated with typewriters and early computer terminals.

In Windows environments, text files typically use CRLF as the standard end-of-line marker. This contrasts with Unix-like systems, which generally use LF alone to denote a newline, and with classic Mac OS, which historically used CR. Modern macOS and many Unix systems have converged on LF, creating cross-platform text-handling considerations for developers and tools.

CRLF also serves as a formal line terminator in many network protocols and Internet standards. Protocols such as HTTP, SMTP, and the older RFC-based specifications require lines to end with a CRLF sequence, ensuring consistent line delimitation across diverse implementations and transport layers.

In programming and data processing, 0x0D0A often appears in source files, network captures, and hex dumps. Many languages represent Windows-style newlines in string literals as "\r\n". Text editors and development environments may automatically translate between CRLF and LF, usually controlled by a “line endings” setting. When transferring text between systems, improper handling of CRLF can lead to formatting issues or parsing errors, highlighting the importance of proper newline conventions in cross-platform workflows.