Patent applications must be prepared according to strict rules that are the result of a large body of statutory law, administrative regulations, and a continuously evolving body of case law. Crafting an allowable patent application that is not overly narrow is a complex and highly technical task, and should only be done by a licensed patent attorney.
Prosecution is the administrative process of obtaining a patent. After an application is filed, it is reviewed to be sure that certain formalities have been followed, and then it is assigned to an examiner. The examiner typically is a scientist or engineer that has expertise in the relevant technology, and has been specially trained in patent law. Examiners conduct a search and render written Office actions to which the applicant or his/her attorney must respond. When the examiner is finally satisfied with the patentability of your invention, he/she will allow the application and a patent will then issue.