Nest personalizes its features for you. After it learns about you and your home, Nest Sense™ automatically balances comfort and energy savings. Programming thermostats is complicated and irritating - but an un-programmed thermostat can waste 20% of your heating and cooling bill. So Nest programs itself. Just turn it up and turn it down. Nest learns what temperatures you like and builds a personalized schedule. Teach it efficient temperatures for a few days and, within a week, it'll start setting them on its own.