Aircraft is a machine which is able to by gaining support from the air or atmosphere on the earth. Tha human activity that surrounds an aircraft is called as aviation. The design of aircrafts is done by many factors such as demand, safety protocols, and physical constraints. They use byoancy to float in the air as the way ships float an water. There are many types of aircrafts and are light weight pistons or gas turbines. Journal Article is sometimes called a Scientific Article, a Peer-Reviewed Article, or a Scholarly Research Article. Together, journal articles in a particular field are often referred to as The Literature. Journal articles are most often Primary Research Articles. However, they can also be Review Articles. These types of articles have different aims and requirements. Sometimes, an article describes a new tool or method. Because articles in scientific journals are specific, meticulously cited and peer-reviewed, journal databases are the best place to look for information on previous research on your species. Without a background in the field, journal articles may be hard to understand - however, you do not need to understand an entire article to be able to get valuable information from it.