In the distant future, when the greenhouse effect has caused a huge disturbance of climate.
In the winter temperature was very low , and the office workers often trembling with cold. 
However in summer it was so hot that people almost melting with heat.

Also it came to that the temperature fluctuated a few times during the day.
Because of that crazy weather, many people were sick and they work with very little performance.

Initially, people thought that the variability of weather and temperature is chaotic 
and no one can predict what temperature will be the next day.

However, after several years of careful observation it was noted the cyclicality of these changes 
depending on the month, season, day or even hours.

The discovery of this allowed the genius researchers to began work on the device, 
which would help people to control the temperature inside the chambers. 

In a short time, the researchers constructed a wonderful machine 
by which temperature inside the chamber is the same throughout the day.

This device is called thermostat.
Principles of operation of the machine are very simple. 	
In termostat there is a thermostat_setting by which you can set the temperature corresponding to your requirements.
The temperature which can be set may vary on time. Time mean date, time, season, or operation.

It is recommended to configure thermostat to control temperature depending on two coordinates: operation or season
which are related to date or hour. In fact operations are related to hours and date, e.g. working hours while seasons depends only on current date.
In thermostat date is defined as month and day of month however today is also treated as date.

If you look closer to those settings you actually came to that seasons depend rightly on months. But operations depend on what the day actually today is.