In this chapter, we will look at one of the basic needs of any application – data. We will learn how to store and retrieve data for use in an application. This chapter will help us understand the different techniques available to store and retrieve data and will also try to answer the question of determining which approach we should use depending on certain requirements.
In this section, we will understand the different sources or origins of a particular piece of data. The data of interest for any application can reside at several locations. For example: