The correlation coefficient is a statistical measure that describes the strength and direction of a relationship between two variables, typically denoted as 'r'.

A correlation coefficient of -1 indicates a perfect negative linear relationship between two variables.

A correlation coefficient of 1 indicates a perfect positive linear relationship between two variables.

A correlation coefficient of 0 indicates no linear relationship between the two variables.

A strong positive correlation is indicated by a correlation coefficient close to 1, meaning as one variable increases, the other variable also increases.

A strong negative correlation is indicated by a correlation coefficient close to -1, meaning as one variable increases, the other variable decreases.

A scatter plot is a graphical representation of two variables, where each point represents an observation, used to visualize the relationship between the variables.