Wikipedia
Insular script was a medieval script system invented in Ireland that spread to Anglo-Saxon England and continental Europe under the influence of Irish Christianity. Irish missionaries also took the script to continental Europe, where they founded monasteries such as Bobbio. The scripts were also used in monasteries like Fulda, which were influenced by English missionaries. It is associated with Insular art, of which most surviving examples are illuminated manuscripts. It greatly influenced Irish orthography and modern Gaelic scripts in handwriting and typefaces.
Insular script comprised a family of different scripts used for different functions. At the top of the hierarchy was the Insular half-uncial (or "Insular majuscule"), used for important documents and sacred text. The full uncial, in a version called "English uncial", was used in some English centres. Then "in descending order of formality and increased speed of writing" came "set minuscule", "cursive minuscule" and "current minuscule". These were used for non-scriptural texts, letters, accounting records, notes, and all the other types of written documents.