Complex sentence: Two quite different approaches to mechanising typesetting were independently developed in the late 19th century, one producing characters on individual type bodies, known as the Monotype system; the other, Linotype, that created slugs, usually comprising a whole line of text.
Split into simpler sentences: Two quite different approaches to mechanising typesetting were independently developed in the late 19th century. One produced characters on individual type bodies, known as the Monotype system; the other, Linotype, created slugs, usually comprising a whole line of text.