Body

Body text is the main reading text, the paragraphs that follow the headline. It is usually the largest amount of text on a page.
Because people read it for longest, body text needs to be comfortable: a readable typeface, a comfortable size, enough line height and good contrast. Around 16 px on screens is a common starting point.
Keep lines from getting too long. Around 45 to 75 characters per line is a useful starting point, because very long lines make it hard to find the next one. Check both with the actual typeface and your readers.