Text-to-Text Alignment

Could someone explain to me what Text-to-Text alignment is used for in paragraph alignment.

I need to explain this further and cannot find an answer, at the moment, doing a Google search.

I do understand what paragraph alignment is and does, but text-to-text I have not come across before.

I am updating Chapter 9 Adding and Formatting Text in the Draw Guide 6.4.

Answer is required urgently so that I can complete this chapter ready for publication.

Regards
Peter Schofield
psauthor@gmail.com