The augur in Ancient Rome was an elected priest and official. The main task performed by the augur involved the interpretation of the will of the gods. The method of divination used by was by observing the behavior of birds and determining what that behavior symbolized. Such readings were taken as a part of any significant decision-making in the society, whether military, economic, or religious.
Things looked for by the augur included all aspects of flight behavior such as direction of flight, solitary flight, flocking, noises made by the birds during flight, and the type of birds being observed. Anything observed could be interpreted as an omen of some description.
The ceremony during which bird behavior was interpreted was known as taking the auspices’. This is where we get our modern English terms auspicious and inauspicious terms from. A problem with the process was that augurs were able to manipulate the results of the readings for their own ends, engineering a bad reading to delay an election, for example.