Often, we refer to good, sound sleep as "a good night's sleep." In slightly more complicated language, we can refer to this as sleep of high quality. Sleep quality is generally considered a good measure of how comfortable or refreshing your sleep was. But what affects our sleep quality in the first place? Have you ever wondered why some people may sleep better than others? Why on some nights do you sleep better? Although genetics also plays a part, our lifestyle habits, sleep environment, and mental health significantly shape sleep quality. Caffeine and sugar consumption also greatly affects sleep, especially for teenagers.