This the finest presentation by which you'll easy have the concept of the sight distance in highways engineering and also you'll learn the types of sight distance in the highways engineering.

3. Sight distance is the length of highway a
driver needs to be able to see clearly. It is
important for drivers on a highway to see
far enough down the highway to recognize
an object in the path and react
appropriately to avoid a crash.

4. 1.Crossing Sight Distance
2.Non- Passing or Non- Overtaking Sight
Distance
3.Passing or Overtaking Sight Distance
4.Lateral Sight Distance

5. Crossing Sight Distance
When two vehicles are coming on
a single lane highway in opposite
direction, and they both are able
to see the each other and avoid
the crash by applying breaks or
any other method is called
crossing sight distance.

6. Non- Passing or Non- Overtaking
Sight Distance
When the distance is 12 meters
between the vehicle and any object
and that object is seen 10 cm above
the surface of road, that distance
will be called as Non- passing or
non overtaking sight distance.

7. Passing or Overtaking Sight Distance
When a vehicle is moving on the
two or three lane highway there is
more opportunities to overtake
the slow moving vehicle when the
distance is available 1.2 meters
then that distance will known as
passing or overtaking sight
distance.

8. Lateral Sight Distance
When a vehicle is moving toward
the an intersection point on
highway and driver is able to see
the coming vehicles form different
directions that king of distance is
called as Lateral sight distance.