Topicalization is a linguistic process that emphasizes a specific part of a sentence by moving it to the front. This technique helps to highlight the topic of discussion, making it clearer for the listener or reader. For example, in the sentence "The book, I read yesterday," the phrase "the book" is topicalized to draw attention to it. In many languages, including English, topicalization can change the focus of a sentence without altering its basic meaning. It is often used in conversation to clarify what the speaker considers important, thereby enhancing communication and understanding between speakers and listeners.