Scar tissue is made of collagen fibers, just like the rest of your skin. The main difference lies in how these fibers are arranged. Scar tissue has a look and feel that is thicker than the rest of your skin because the collagen is produced as a disorderly mass of fibers.
A pre-order is an order placed for an item which has not yet been released. The idea for pre-orders came when people found it hard to get popular items in stores due to their popularity. Companies then had the idea to allow customers to reserve their own personal copy, before the release, which has been a huge success.
The definition of a steward is an employee who is charge of the management of a very big house or a person who is responsible for the food and drink staff at a restaurant.The definition of a steward is an employee who distributes food and drinks.