(also just called "bold")
What Is Bold Type?
In type or printed writing, bold is a heavy kind of writing. The characters are thicker than normal, as you see in the diagram below.
When To Use Bold
We use bold for emphasis, when we want to make sure that our reader sees and takes in certain words. The main examples are:
It is better not to write entire paragraphs in bold. It is not easy to read a lot of words all together in bold (like this paragraph). So if you want readers to read your writing, better reserve bold for a few important words and phrases only.
Note that in handwriting and typewriting, emphasis can usually be shown with underlining.
Like italics, bold is not really possible in handwriting. Bold is used in "type", which is the kind of writing you usually see in books and newspapers and on a computer screen.