Underlines are generally divided into single underline, double underline, bold underline, dashed line below and so on. In some documents, underlining is usually used to enhance attention. On the other hand, in web pages, the text that can be connected (hyperlinks) is generally underlined. The underline is a straight line, which means that it is now below the word.

Underline is also a punctuation mark, also known as underline, lower horizontal line, lower wavy line and so on. When writing, editing or printing text, it is usually used to emphasize, divide or indicate the role of spaces. Underline originated in the era of handwriting. When we want to emphasize a word or phrase, we will draw a line under it. This line is underlined.

Examples of underline usage:

1, emphasis: Underline can be used to emphasize a word, phrase or the whole sentence to make it more eye-catching. Such as: "This book is really _ good _!" The word "good" in the book is underlined. For example, a module should have a short lowercase name and no responsibility. For example, peace is the most important thing. The way of keeping in good health: Laughter nourishes the heart and depresses the "hurt" heart. Pay attention to health, the first is to cultivate the heart. Early health care, late health care, lifelong health care, lifelong health; Lifelong health, lifelong corning. I wish you the best of health!

2. Division: Underline can be used to divide different contents in a web page or document, such as dividing different paragraphs, subheadings, signatures at the bottom of the page, etc. For example, the practice of.

3. Spaces: Underscores can also be used to indicate spaces, which are usually used in the URL or file name of a website, such as "my_file_name.txt".