Lorem Ipsum is simply dummy text of the printing

It is a long established fact that a reader will be distracted by the readable content of a page when looking at its layout. The point of using Lorem Ipsum is that it has a more-or-less normal distribution of letters, as opposed to using 'Content here, content here', making it look like readable English.Lorem ipsum, or lipsum as it is sometimes known, is dummy text used in laying out print, graphic or web designs. The passage is attributed to an unknown typesetter in the 15th century who is thought to have scrambled parts of Cicero's De Finibus Bonorum et Malorum for use in a type specimen book. In particular, the garbled words of lorem ipsum bear an unmistakable resemblance to sections 1.10.32–33 of Cicero's work, with the most notable passage excerpted below:

“Neque porro quisquam est, qui dolorem ipsum quia dolor sit amet, consectetur, adipisci velit, sed quia non numquam eius modi tempora incidunt ut labore et dolore magnam aliquam quaerat voluptatem.”
A 1914 English translation by Harris Rackham reads:

“Nor is there anyone who loves or pursues or desires to obtain pain of itself, because it is pain, but occasionally circumstances occur in which toil and pain can procure him some great pleasure.”
McClintock's eye for detail certainly helped narrow the whereabouts of lorem ipsum's origin, however, the “how and when” still remain something of a mystery, with competing theories and timelines.
So how did the classical Latin become so incoherent? According to McClintock, a 15th century typesetter likely scrambled part of Cicero's De Finibus in order to provide placeholder text to mockup various fonts for a type specimen book.

It's difficult to find examples of lorem ipsum in use before Letraset made it popular as a dummy text in the 1960s, although McClintock says he remembers coming across the lorem ipsum passage in a book of old metal type samples. So far he hasn't relocated where he once saw the passage, but the popularity of Cicero in the 15th century supports the theory that the filler text has been used for centuries.

And anyways, as Cecil Adams reasoned, “[Do you really] think graphic arts supply houses were hiring classics scholars in the 1960s?” Perhaps. But it seems reasonable to imagine that there was a version in use far before the age of Letraset.