Data independence is a concept that has been around for a long time, but it can take much work to wrap your head around. A system's data independence separates data from processing and presentation applications. Data independence is often an innate function of the system's diverse components; however, data may be restricted to a single application. In other buzzes, if you want to use data—like an address or phone number—to display on a screen or use in an algorithm, you shouldn't have to worry about where it came from. You need to know what it is, so if someone changes the source (for example, they update their contact information), you don't have any problems with your program. Database systems are all about data. They hold, organize, and make it available to other applications. What if you need to use that same data in more than one application? That's where the concept of data independence comes in. Data independence allows you to use the same set of data across multiple applications without having to rewrite code for each one. It will enable you to separate your code from your data, which means less time wasted on maintenance and more time spent doing something useful! Data is the currency of the future. The oil makes our world go round, and it's everywhere. We sometimes need to figure out what to do with it. We're all familiar with big data—the term used to describe datasets that are so large they cannot be processed by conventional software. What about small data? What can we do with that? Well, there's a lot! Small data is just as necessary as big data because it has uses and applications. Small data can be used to find an apartment or order food at a restaurant. Small data can also help you make better decisions about your life since it allows you to understand yourself better than ever possible through analytics and behavioral patterns derived from your previous actions. Small data also allows companies access to their customers' lives in new ways, which helps these companies provide better services and products for their clients' enjoyment!