Correlation doesn't imply causation
A correlation research doesn't do any experimentation but uses survey, interviews, observations of behaviour as tools.
They looks like for pattern of correlation
A fundamental difference between experimental research and correlational research is that in correlational research there is no Independent variable (no groups)
Sometimes are they referred as study because no variable is manipulated (no independent variable)
A positive correlation (the slope of the line is going up)
A research that implies a quasi-independent variable is also a correlational research because the notion of randomness is not present.