The number "0.0001" is a decimal that represents one ten-thousandth of a whole. In fraction form, it can be expressed as 1/10,000. This value is often used in scientific measurements, financial calculations, and various fields where precision is important. In the metric system, "0.0001" can also be related to micro units, as it is equivalent to 100 micro units. For example, in terms of meters, 0.0001 meters is the same as 0.1 millimeters, which is a very small length often used in engineering and manufacturing.