Answer to Question 1
Relational database is the most widely used database model that organizes information into tables of records. The records are related to one another by linking a field in one table to a field in another table with matching data. This approach separates the data from the paths to retrieve them, thus making the database less dependent on the hardware and its particular operating system. These relational databases continue to improve, each adding support for large files containing images, video, or audio. Relational systems now also support XML data types, as well as spatial information and mapping coordinates. This makes relational databases a standard in most organizations.
Answer to Question 2
An organization's culture plays an important part in choosing a particular software development strategy. Moving to an agile development approach, for instance, means much more than programming in pairs or adopting the colorful Scrum vocabulary. It is a cultural shift that many development teams may find uncomfortable. Agile methods need developers who welcome changes in requirements, because they understand that the ultimate goal is to develop software that users really want, not just to finish a project on time. On the other hand, the waterfall method stresses sequenced tasks, so developers who complete their task on time consider themselves successful even if the project itself is falling behind. But agile teams are collectively responsible for delivery, and team members must help one another achieve the goal to be successful. The team must be cohesive and trusting, since each member's job and career may depend on the whole team's performance.