PL / SQL procedure calls

Studying PL / SQL I came across the following code:

CREATE PROCEDURE incluir_segmercado(p_id IN NUMBER , 
                                    p_descricao IN VARCHAR2)

IS
BEGIN 
    INSERT INTO segmercado
        values(p_id, UPPER(p_descricao));
    COMMIT;
END;

EXECUTE incluir_segmercado(3, 'Farmaceutico')

BEGIN 
    incluir_segmercado(4, 'Industrial');
END;

The author used 2 ways to call the procedure created above, but did not explain the difference between calling EXECUTE and calling BEGIN, is there any kind of difference between calls?