The Chi-Square Test is used to determine whether there is an association between two categorical variables (i.e., whether the two variables are independent or related). To perform a Chi-Square Test, the two categorical variables are displayed in a crosstab where each cell shows the frequencies of the combination of the categories of both variables. SPSS will then compare the observed and expected frequencies in each cell to calculate the result of the test. The only assumption concerns your sample size: the expected number of observations in each cell should at least be 5.