Enter key together to make a line break.
Enter key by itself to make a new paragraph.
Understanding the Post Editor
To save you from having to type paragraph tags in your posts and pages, WordPress automatically converts line breaks into paragraphs and new lines into line breaks. Explanation:
In the Text editor
Leaving an empty line between 2 lines will automatically convert them into separate paragraphs, while continuing on the next line will convert it into a line break. Typing the following..
Here is a paragraph of text. Here is the 2nd paragraph, separated by an empty line. This is a new paragraph with a line break
..will result in the following HTML output:
<p>Here is a paragraph of text.</p> <p>Here is the 2nd paragraph, separated by an empty line.</p> <p>This is a new paragraph<br/> with a line break</p>
In the Visual editor
Enter (Return) key will end the paragraph you are writing and start a new one. If you want to start a new line without creating a new paragraph, press the
Enter keys together.
Keep in mind that if you write paragraph tags (
<p>) in the HTML editor and switch to the Visual editor and back, WordPress will strip out the tags. If you only want to write HTML for a page or post, consider using the Disable Visual Editor WYSIWYG plugin.