An inequality that compares two quantities that are strictly not equal is called a strict inequality. There are two types of strict inequalities. The boundary values in strict inequalities are not included in the solution set. On the other hand, an inequality that compares two quantities that are not necessarily different is called a non-strict inequality. There are two types of non-strict inequalities. The boundary values in non-strict inequalities are included in the solution set. Consider the graphs of several examples of strict and non-strict inequalities. It can be seen that in order to indicate strict inequalities graphically, an open point $(\circ )$ is used for number line inequalities and a dashed boundary line or curve is used for two-dimensional inequalities. To indicate non-strict inequalities graphically, a closed point $(\bullet )$ is used for number line inequalities and a solid boundary line or curve is used for two-dimensional inequalities.