Encoding is the process of transforming information from one format into another. The opposite operation is called decoding. Character encoding or character set (sometimes referred to as code page) consists of a code that pairs a sequence of characters from a given set with something else, such as a sequence of natural numbers, octets or electrical pulses, in order to facilitate the storage of text in computers and the transmission of text through telecommunication networks. Common examples include Morse code, which encodes letters of the Latin alphabet as series of long and short depressions of a telegraph key; and ASCII, which encodes letters, numerals, and other symbols, both as integers and as 7- bit binary versions of those integers, generally extended with an extra zero-bit to facilitate storage in 8-bit bytes (octets). A semantics encoding is a "translation" between formal languages. For programmers, the most familiar form of encoding is the compilation of a programming language into machine code or byte-code. Conversion between document formats are also forms of encoding. Compilation of TeX or LaTeX documents to PostScript are also commonly encountered encoding processes. Some high-level preprocessors such as Objective Caml's, Camlp4 or Apple Computer's WorldScript also involve encoding of a programming language into another. Text encoding uses a markup language to tag the structure and other features of a text to facilitate processing by computers. A markup language combines text and extra information about the text. The extra information, for example about the text's structure or presentation, is expressed using markup, which is intermingled with the primary text. The best-known markup language in modern use is HTML (HyperText Markup Language), one of the foundations of the World Wide Web. Originally markup was used in the publishing industry in the communication of printed work between authors, editors, and printers.