Each time the key is pressed, the paragraph formatting in the previous paragraph is carried forward to the next paragraph.

Enter or Return key

Explanation:

In many applications such as Microsoft Word, when editing or creating a text layer in a document, pressing the 'Enter' key, or alternatively known as 'Return' key, sends the cursor to the next line or creates an entirely new line which may by consequence create a new paragraph.  

PS: For programs such as MS Word, pressing the enter key may move to the next paragraph rather than a new/next line. In such programs,  to go to the next line,  'Ctrl' key followed by 'Enter' key should be pressed.

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