What is the meaning of ?

Beginning of a section of text.

Beginning of a paragraph; paragraph break; hard return.

Used inline inside a quotation of a multi-paragraph text where dividing into paragraphs is not allowed. Thus, "Blah ¶ Blah blah blah ¶ Blah blah blah."

Used as an index representing "paragraph" followed by a number. Compare the analogous use of the section sign §.

Source: wiktionary.org