Kinetic energy is the energy of motion. Any object that is moving possesses kinetic energy. Baseball involves a great deal of kinetic energy. The pitcher throws a ball, imparting kinetic energy to the ball. When the batter swings, the motion of swinging creates kinetic energy in the bat. The collision of the bat with the ball changes the direction and speed of the ball, with the idea of kinetic energy being involved again.
As stated in the kinetic-molecular theory, the temperature of a substance is related to the average kinetic energy of the particles of that substance. When a substance is heated, some of the absorbed energy is stored within the particles, while some of the energy increases the motion of the particles. This is registered as an increase in the temperature of the substance.
At any given temperature, not all of the particles of a sample of matter have the same kinetic energy. Instead, the particles display a wide range of kinetic energies. Most of the particles have a kinetic energy near the middle of the range. However, a small number of particles have kinetic energies a great deal lower or a great deal higher than the average (see figure below).  The blue curve in the figure above is for a sample of matter at a relatively low temperature, while the red curve is for a sample at a relatively high temperature. In both cases, most of the particles have intermediate kinetic energies, close to the average. Notice that as the temperature increases, the range of kinetic energies increases and the distribution curve "flattens out". At a given temperature, the particles of any substance have the same average kinetic energy.
As a sample of matter is continually cooled, the average kinetic energy of its particles decreases. Eventually, one would expect the particles to stop moving completely. Absolute zero is the temperature at which the motion of particles theoretically ceases. Absolute zero has never been attained in the laboratory, but temperatures on the order of \(1 \times 10^{-10} \: \text{K}\) have been achieved. The Kelvin temperature scale is the scale that is based on molecular motion, and so absolute zero is also called \(0 \: \text{K}\). The Kelvin temperature of a substance is directly proportional to the average kinetic energy of the particles of the substance. For example, the particles in a sample of hydrogen gas at \(200 \: \text{K}\) have twice the average kinetic energy as the particles in a hydrogen sample at \(100 \: \text{K}\). Summary
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LICENSED UNDER Temperature affects the kinetic energy in a gas the most, followed by a comparable liquid, and then a comparable solid. The higher the temperature, the higher the average kinetic energy, but the magnitude of this difference depends on the amount of motion intrinsically present within these phases. IN GASES In general, the average kinetic energy increases at higher temperatures for gases. Since gases are quite compressible, the effects of higher or lower temperature are significant.
IN LIQUIDS For liquids and solids, it is much simpler. Since liquids have intermolecular forces binding them together, temperature really only affects the strength of those intermolecular forces, since those forces are restricting the effects of the change in average kinetic energy. As temperature increases, the average kinetic energy of the liquid molecules increases until the intermolecular forces break. You won't often see noticeable changes in the volume or looseness of the liquid, since they are fairly incompressible. When the intermolecular forces break and we get to the boiling point, that's when you can have more freely-moving particles, but even then, anything still in the liquid form is still fairly incompressible. IN SOLIDS For solids, the rigid nature of the lattices the particles are in restricts their kinetic energy from affecting much of the average motion in the solid. As temperature increases, the average kinetic energy increases, but we will see hardly any obvious difference in volume or shape. When we approach the melting point, the lattice energies break and allow the particles to move slightly more freely, but still leaving them fairly incompressible. For solids, temperature changes, in the absence of induced phase changes, usually just manifests itself as temperature changes, and nothing else.
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When temperature increases the kinetic energy of particles decrease?
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