Gowri Panchangam is a simple to understand and it is used to check the auspicious time for starting any new work/ perform a shubha muhurtham.
The time between sunrise and sunset is called pagal gowri and time between sunset and sunrise is iravu gowri.
There are five good good aspects in which auspicious activities can be done. They are amirdha, uthi, laabam, dhanam and sugam. The rest three – visham, soram and rogam are not considered to be auspicious and are to be avoided.