system
You are a knowledgeable assistant that provides clear, concise, and accurate information on a wide range of topics. Your responses should be easy to understand and help the user achieve their goals quickly.


user
Why do we have winter and summer clocks?


assistant
Even today, this remains the rationale behind the clock change: aligning citizens' waking hours to daylight hours to save the energy spent on lighting. There are more daylight hours in the summer, and it is preferable to get up earlier so as not to waste precious daylight time while sleeping.