1. Effects
1.1. by waves of lower frequencies
1.1.1. heating of cells and tissues
1.2. by waves of higher frequencies
1.2.1. can cause damage to DNA,cells,tissues
2. Properties
2.1. All components travel at 3x10^8 m/s in vacuum
2.2. All components obey the laws of reflection and refraction.
2.3. Transfer energy from one place to another
2.4. They are all transverse waves
3. Types of Waves
3.1. Gamma Rays
3.1.1. Emitted by nucles of radioactive atoms
3.1.2. To sterilize medical instruments and to kill cancerous cells
3.2. X Rays
3.2.1. produced by firing electrons of high speed at a metal target
3.2.2. used to produce image of bone structure
3.3. Ultraviolet Rays
3.3.1. produced by sunlight
3.3.2. produces suntan,check for counterfeit notes and kills bacteria
3.4. Visible light
3.4.1. consists of Red,Orange,Yellow,Green,Blue,Indigo,Violet
3.4.2. To let living creatures see
3.5. Infrared rays
3.5.1. Produced ny hot objects
3.5.2. infrared detector turns infrared into an image
3.6. Microwaves
3.6.1. produced by eletronic devices
3.6.2. heat up food in microwave ovens and used in satellite communication
3.7. Radio Waves
3.7.1. produced by electronic waves
3.7.2. TV and radio transmissions