These are the highest energy electromagnetic waves and can penetrate through several centimeters of lead.
Wavelength
They are electromagnetic waves, with the shortest wavelength and they are shorter than about 10 trillionths of a meter. The only way it can change is by going backwards on the electromagnetic spectrum to some higher wave or ray.
Energy
Both x rays and gamma rays are used in a technique called radiation therapy to kill diseased cells in the human body. Radiation is a high level of an energy substance that can be harmful for humans. If you control how much radiation of these rays you take in, than it will not be harmful.
Frequency
The range of frequencies is 3x10^19 in Hz. They have more wavelengths in a frequency than any other wave or ray. Hertz=Hz and that is how frequency is measured
More Information
Hertz=Hz and that is how frequency is measured. They are the most dangerous rays you can use against your body, and that is why it is good for you to protect your skin, when your skin is exposed to the gamma rays. They are produced from the decay of excited nuclei of radioactive elements.