Well , as the link you posted explains it refers to the likelihood of a given result if in fact the null hypothesis is true . For example , if I find that boys are 4 inches taller than girls on average in a given sample p . 05 means there is a 5 % chance there is no real difference in height between boys and girls and my sample is just skewed . There is 95 % likelihood I have detected a real difference and that boys truly are taller on average in the population I sampled . This is the generally accepted standard for statistical significance . It does not AT ALL mean that the results are untrue for 5 out of 100 cases or that 5 out of a hundred boys don ' t fit the model and are shorter as you have insinuated above .