The document discusses textual cohesion and the various linguistic devices that contribute to cohesion in a text. It defines cohesion as the links between different parts of a text that distinguish it from a random sequence. There are five main cohesive devices: reference, substitution, ellipsis, conjunction, and lexical cohesion. Reference involves pronouns and other words that refer back to things mentioned earlier. Substitution and ellipsis involve replacing or omitting words to avoid repetition. Conjunctions link different parts of a text, while lexical cohesion uses repetition of words to create links. Together these devices help create a coherent text by connecting its various parts through linguistic and semantic relationships.