敲黑板划重点 (qiao hei ban hua zhong dian)
敲黑板划重点 means knocking on the blackboard to focus. The word is usually followed by other information, aiming to emphasize the importance of what to say next. This is a concise summary of important information for everyone. The source of this word is that teachers especially like to use chalk to knock on the blackboard to make students focus which almost everyone has experienced in school.
After this word becomes popular, in addition to becoming the spoken language used by netizens, some mainstream news media often uses the word as the title of the article.