What do you mean by Tangent, Secant and Chord of a circle?

Understand Tangent, Secant and Chord of a circle. Click on the link to Watch the VIDEO explanation: 
Watch Video

Tangent, Secant and Chord of a circle 
Definition of Tangent, Secant and Chord of a circle 
A line in the plane of a circle and having one and only one point common with it is known as tangent of the circle. 
The common point is called the point of contact. 
Here, O is the center of the circle, line l is the tangent and A is the point of Contact. 
A line which intersects a circle at two points is called a secant to the circle. 
Line m is the secant and it intersects the circle at A and B. 
A segment whose endpoints lie on the circle is called a chord of the circle. 
AB is the chord to the circle.