Heat, is the thermal energy transferred from a hotter system to a cooler system that are in contact. Thus, heat is a form of energy which raises temperature of matter, increases volume of matter, changes state and physical properties of matter and brings about chemical change. Temperature is defined as the degree of hotness or coldness of a body. Thermodynamics is the branch of physics that deals with heat and temperature, and their relation to energy, work, radiation, and properties of bodies of matter. The behavior of these quantities is governed by the four laws of thermodynamics. The article Heat and Thermodynamics discusses some basic concepts of heat and thermodynamics.

Latent Heat: It is the heat required to change the state of a substance from solid to liquid from liquid to gas without change in temperature.
Heat and Temperature: Temperature is the degree of heat of a body/substance which can be measured by various scales like Centigrade [latex]{(^oC)}[/latex] and Fahrenheit [latex]{(^oF)}[/latex]. The relation between Fahrenheit and Celsius scale is [latex]T_{F}[/latex] = [latex]\frac{9}{5}T_{C}+32[/latex] The relation between Kelvin and Celsius scales is [latex]T_{C}[/latex] = [latex]T-273.15[/latex]
Thermometer: It is a system with a conveniently observed macroscopic property that changes with temperature. It could be length of mercury column, gas pressures, electrical resistance, or the bending of a bi metal strip in a dial thermometer. The zeroth law guarantees reliability, in that two systems for which the thermometer gives the identical reading must have the same temperature.
Evaporation: Evaporation is the change of state from liquid to vapor and thereby results in cooling. Rate of evaporation is affected by wind, heat and surface area.
Transfer of Heat: There are three Heat transfer mechanisms
Conductivity: It is a property experienced by metals. The process of heat transfers without visible motion of the atoms or molecules from a region of higher temperature to that of lower temperature. It is the transmission of heat from molecule to molecule.
Radiation: Radiation is the transmission of heat from one point to another point without heating the medium, that is, transmission of heat by means of waves without the help of a medium.
Convection: It transmits the heat of heated matter, that is, by actual motion of the heated particles of a liquid or gas.
Laws of Thermodynamics: These laws show how heat energy can be passed from one body to another.
Zeroth Law: No heat will flow between two bodies that are of the same temperature. In other words, a body's temperature doesn't depend on the material involved.
First Law: Internal energy can be added to a body either by heating or doing work on it, and conversely, if work is extracted from the body, its internal energy will fall unless an equivalent amount of heat is supplied from outside. This reinforces the law of Conservation energy.
Second Law: Heat will not pass spontaneously from a cold body to a hotter body.
Third Law: It is impossible to cool a body right down to absolute zero, that is, below -273.15[latex]{^oC}[/latex].