The rising and setting Sun.

The Sun rises in the East and sets in the West, yes?...NO.  It only does this at two points in our year.

Equinox - sun rises due east and sets due west.  

These are around 21 MAR and 21 SEP in the Northern Hemisphere - they are the days of equal day and night hours.  In between it gets darker and lighter as the tilted earth moves one cycle around the sun. If the earth did not tilt we would not have Seasons.

Winter solstice - Shortest Daylight hours at midwinter around 21 DEC....There is a  low arc as we tilt away from sun in northern hemisphere - sun rises nearer south east and sets nearer south west - ie it arcs over the south - at midday the sun will indicate which way is south.

Summer solstice - Midsummer is around 21 JUN . There is a higher arc so sun seems higher overhead at midday - rises nearer north east, sets nearer north west.