Diple (textual symbol)
Diple (Ancient Greek: διπλῆ, meaning double, referring to the two lines in the mark >) was used in margins to draw attention to something in text. It is sometimes also called antilambda because the sign resembles a Greek capital letter lambda (Λ) turned upon its side. In some ways its usage was similar to modern day quotation marks; guillemets (« »), used for quotations in French, are derived from it.
Isidore remarks in his Etymologiae (I.XXI.13)  that the diple was used to mark quotations from the Bible. He also talks about diple peri strichon (or sticon), which was used to draw attention to separate concepts and diple periestigmene used (like obelos) to mark dubious passages. Diple obolismene was used according to Isidore to separate sentences in comedies and tragedies, so its usage was similar to that of paragraphos.