As with everything else, the size, shape and feel of the breast differ from woman to woman. The way a normal breast feels will depend on the age of the woman, where she is in her menstrual cycle, her weight and exercise habits, genetics, medication, pregnancy, and use of the pill. The breast is made up of fat over and between sections of gland and connective tissue. The fat is what makes the breasts different sizes.
Younger women tend to have firmer, harder breast because the tissue is denser.
Some women's breast get softer as they age. Some women have lumpy breasts. This is all normal. Most women experience swelling, discomfort or lumpiness in the breast right before, or during their period. This is due to changes in hormone levels that cause the breast to retain fluid.