A polynomial is an algebraic expression consisting of multiple terms. The terms of a polynomial can be variables or variables raised to a power of a whole number, a constant or the product of these two.
The real number that precedes the variable is called the coefficient.
A polynomial involving one variable is called a polynomial in one variable.
The highest power of the variable of a polynomial is called the degree of the polynomial.
Based on its degree, a polynomial can be called as linear polynomial, quadratic polynomial, cubic  polynomial and so on.
The general form of a is , where  and  are real numbers and
The general form of a  is , where and  are real numbers and
The general form of a  is , where  and  are real numbers and
The value of a polynomial  when  ( is a real number) is the value obtained by substituting  as . It is denoted by .
The zero of the polynomial is defined as any real value of x, for which the value of the polynomial becomes zero.
A real number  is a zero of a polynomial , if .

Geometrical Meaning of the Zeroes of a Polynomial: The zero of the polynomial is the -coordinate of the point, where the graph intersects the -axis. If a polynomial  intersects the -axis at , then  is the zero of the polynomial.
The graph of a linear polynomial intersects the x-axis at a maximum of one point. Therefore, a linear polynomial has a maximum of one zero.

The graph of a quadratic polynomial intersects the x-axis at a maximum of two points. Therefore, a quadratic polynomial can have a maximum of two zeroes. In case of a quadratic polynomial, the shape of the graph is a parabola. The shape of the parabola of a quadratic polynomial  depends on .
If , then the parabola opens upwards.
If , then the parabola opens downwards.

The graph of a cubic polynomial intersects the -axis at maximum of three points. A cubic polynomial has a maximum of three zeroes. In general, an nth-degree polynomial intersects the x-axis at a maximum of n points. Therefore, an nth-degree polynomial has a maximum of n zeroes.