In order to operate the transistor in the desired region, we have to apply an external dc voltage of correct polarity and magnitude to the two junctions of the transistor. This is called biasing of the transistor.
When we bias a transistor, we establish a certain current and voltage conditions for the transistor. These conditions are called operating conditions or dc operating point or quiescent point. This point must be stable for proper operation of transistor. An important and common type of biasing is called Fixed Biasing. The circuit is very simple and uses only few components. But the circuit does not check the collector current which increases with the rise in temperature.
Bio-Medical Engineering-Lecture Notes