Widgets are partial shortcuts of programs which sometimes give information on the home screen without opening the program.
Widgets are programs running on the home screen displaying information at a glance like time, weather, battery status, Music playing, status & turning ON/OFF the WiFi, Bluetooth, internet etc. Some of the widgets come built-in along with the OS whereas others can be downloaded from internet.
By placing the widget on the Home screen, you keep the program on. The more number of widgets on the home screen, more number of programs are running and you will have faster battery drainage. So, if your battery is running out fast, you may want to remove some widgets from home screen ( no need to uninstall, just remove from home screen)
KW: Widgets, Android, mobile, phone