Observation is the primary tool used for collecting and recording data. Scientists rely on observation to determine the results of theories. Hypotheses are tested against observation using tools or human senses.
Observation has been used by scientists since at least as early as ancient Greece. Observations of earthworms led many philosophers and scientists to learn how to identify and quantify results of scientific studies. This form of inquisition helped lead scientists to be able to test new theories as different methods of observation were developed. New forms of observation occur as technology advances. This broadens the capacity for observation and scientific inquiry.
Observation is not limited to scientists. It is also one of the primary ways in which humans and animals learn how to interact in their respective environments. Observation is when something is noticed and is then recognized as being important. This process helps on basic levels of survival, such as an individual's understanding not to walk out into a busy street without looking for oncoming traffic.
Animals follow similar basic levels of observation. If an animal sees other animals feeding in a specific location, it recognizes the behavior as a clue to a possible meal. Scientists typically rely on instruments to help them create observations on a more objective level.