When you feel a static shock, you are feeling the generation of 3,000 volts of electricity. You will feel the electrostatic discharge of 3,000 volts, but smaller charges can damage electronic components, and you won't even be aware that a discharge has occurred. Some more sophisticated components can be damaged by charges as low as 10 volts. You should be aware of the relative sensitivity to ESD damage of the devices you may be working on/with.
As electronic technology advances, electronic components tend to become smaller and smaller. As the size of the components is reduced, so is the microscopic spacing and insulators and circuits within them, increasing the sensitivity to ESD. As you can see, the need of proper ESD protection increases everyday.
Many of the your daily activities may generate charges from your body that are potentially harmful to components, such as:
Even moving objects on your workstation can generate hundreds of volts. The amount of static electricity also depends on the humidity of the environment. Low humidity conditions such as those created when air is heated in the winter will also promote the generation of significantly high voltages which can damage components.