Nineteenth-century schoolchildren chanted the alphabet past Z to a 27th character, and the slurred phrase they used to name it, and per se and, gave us the word ampersand. This episode follows the symbol from first-century Roman cursive, where scribes fused the letters of the Latin word et, to its role in modern code.

We cover the survival of the et ligature through Carolingian minuscule and Renaissance type, the false Ampere etymology, cousins like the Tyronian et on Irish and Scottish signs and the plus sign, the Writers Guild rule that distinguishes an ampersand from a spelled-out and in screen credits, APA versus MLA citation rules, and the ampersand's roles in C++, memory addresses, HTML entities, Unix shells, and URL query strings.

• Why a logogram for et survived the purge of messy ligatures when scripts were standardized un ...