The Methods section describes the means by which the research was conducted; that is to say, it describes how the empirical information was gathered. A Methods section can also explain the theory upon which the research was based, and describe how this theoretical approach was put into practice. When applicable, this section should also include information about ethical considerations. The Methods section is usually written in the past tense.
In the sciences, the methods used should be described in enough detail for the reader to be able to replicate the research. This section usually also lists the materials used in the experiments, and therefore a combined Materials and Methods section is often used.