Temperature is the physical quantity based on the measure of which, heat energy flows between two bodies. Heat energy flows from a body having higher temperature to the body of lower temperature.
Temperature is the degree of the measure of hotness or coldness in a body in any physical state (solid, liquid or gas).
Temperature is like the physical quantity "height" that is a measure of the gravitational potential energy. By knowing the temperature, we can calculate the quantity of heat energy in a body.
Temperature is a scalar quantity.