What the summary table shows belows is more statistics on birthweight and habits of the mother. The mean weight is giving in grams and it shows that for smoking mothers the average birth weight is lower than that for non smoking moms. The median is the 5th row and shows that the median birth weight was again lower for the smoking mothers than the non smoking mothers. Also the max weight for the babies of the smoking mothers was smaller than the max weight for the non smoking mothers. This shows that there is an association with lower birth weights with mothers who smoke.