A vector quantity is simply represented by placing an arrow on the corresponding letters e.g. $\overrightarrow { A }$

**1. Equal Vector:** Two vectors showing the same magnitude and the same direction are called to be **equal vectors**.

**2. Negative Vectors:** A vector having the same magnitude but directed in the opposite sense to a given vector is called the neagtive vector and is represented with a minus sign.

**3. Null Vector or Zero Vector:** If the magnitude or modulus of a vector is zero it is called a null vector i.e., $\left| \overrightarrow { A } \right| $= 0.

**4. Unit Vector:** A vector whose magnitude is unity is called a unit vector . A unit vector in the direction of vector $\hat { A } $.$\hat { A } $ stands for A cap.

Hence, $\hat { A } $=$\frac{\overrightarrow { A }}{\left| \overrightarrow { A } \right|} $

**5. Like Vectors:** The vector directed in the same sense irrespective of their magnitude are called like vectors.

**6. Collinear Vectors:** Two or more vectors parallel or antiparallel to each other are called collinear vectors.

**7. Co-intial Vectors:** Vectors drawn from the same initial point are called co-initial vectors.

**8. Coplanar Vectors:** Vectors whose line of action lies in the same plane, i.e., if they lie in the same plane, they are called coplaner vectors and the plane is which the vectors are lie are called the plane of vectors.

**9. Position Vectors:** The vectors which are used to specify the position of a point P with respect to some fixed point O[origin] represented by OP, is known as position vector. The distance from the origin can be expressed as $\overrightarrow { r } =xi + yj +zk$ ,where x, y and z are the coordinates of the point P and the vector r is the position vector $\overrightarrow { r }=\overrightarrow { OP } $ .