Law is a very diverse field and students choose their own field of expertise depending upon the field in which they wish to practice. Therefore, essay assignments they need to undertake can range from property law to constitutional law, criminal law or corporate law. The topics to be addressed in these fields differ widely. In some countries, some fields of law are ruled by case law while others though legislature. While students will need specialized knowledge of their own chosen fields of law study, some general areas are common to all law studies. Students should possess a deep understanding of all laws, by laws, judiciary systems, and branches of law as Roman dutch law, commonwealth law, English law, Shariah law etc. for effective essay writing.