in many programming languages that symbolizes that the given identifier represents a constant. Surnames A practice exists (most commonly in Francophone countries) of distinguishing the surname from the rest of a personal name by stylizing the surname only in all caps. This practice is also common among Japanese, when names are spelled using Roman letters. Military communication In April 2013, the U.S. Navy moved away from an all caps-based messaging system, which was begun with 1850s-era teleprinters that had only uppercase letters. The switch to mixed-case communications was estimated to save the Navy $20 million a year and is compliant with current Internet protocol. Contract law An antiquated practice that still remains in use, especially by older American lawyers who grew up before the arrival of computers, is to use all caps text for text that is legally required to be emphasised and clearly readable. The practice dates to the period of typewriters, which generally did not offer bold text, small capitals, or the opportunity to add marginal notes emphasising key points. Legal writing expert Bryan A. Garner has described the practice as "ghastly". A 2020 study found that all-caps in legal texts is ineffective and is, in fact, harmful to older readers. In 2002, a US court spoke out against the practice, ruling that simply making text all-capitals has no bearing on whether it is clear and easily readable: Lawyers who think their caps lock keys are instant "make conspicuous" buttons are deluded. In determining whether a term is conspicuous, we look at more than formatting. A term that appears in capitals can still be inconspicuous if it is hidden on the back of a contract in small type. Terms that are in capitals but also appear in hard-to-read type may flunk the conspicuousness test. A sentence in capitals, buried deep within a long paragraph in capitals will probably not be deemed conspicuous...it is entirely possible for text to be conspicuous without being in capitals. Readability Miles Tinker, renowned for his landmark work, Legibility of Print, performed scientific studies on the legibility and readability of all-capital print. His findings were as follows: All-capital print greatly retards speed of reading in comparison with lower-case type. Also, most readers judge all capitals to be less legible. Faster reading of the lower-case print is due to the characteristic word forms furnished by this type. This permits reading by word units, while all