There are many styles of introductions, but they all have three general components in common, usually in this order.
This is a sample of a simple, but perfectly decent introduction. If you are writing a paper other than your master's thesis, this type of introduction is perfect.
If you are writing a scientific or research-based paper your introduction might include
Source: Made by Ms. K
This shows a complex introduction in action. Notice this is only the introduction to this study and it has multiple paragraphs. This type of introduction is used when revealing the findings of an intensive scientific experiment/study or an extensive research project.
Source: Analysis by Ms. K introduction used from http://www.jmir.org/2011/1/e26/