A database is a sorted collection of structured information so that it can be easily accessed and controlled. DB is the short form of a database. It is usually controlled by a database management system (DBMS). Data in databases is typically stored in the form of rows and columns in a series of tables to make effective processing and querying of data. By maintaining, the data in the form of tables, it can be easily accessed, managed, modified, updated, organized, and controlled.Evolution of DatabaseDatabases were introduced in the early 1960s. Since then, they have evolved dramatically. Navigational databases, follow a hierarchical structure that is dependant on a tree-like modal and stick to on-many relationships. On the other hand, a network database sticks to multiple relationships and is kind of more flexible. These were the original systems and were more inflexible. Eventually, relational databases became popular in The 1980s. After that object-oriented databases came in the 1990s. Henceforth, NoSQL databases came, and now cloud databases and self-driving databases are gaining popularity.Database SoftwareDatabase software helps in creating, editing, and maintaining database files and data. It helps in enabling easier file and record creation, data manipulation, and reporting. The software also controls data storage, backup, reporting, and security. Database security is one of the major concerns today, as data theft is more prominent these days. It is sometimes referred to as a “database management system”(DBMS).Different Types of DatabaseThe organization decides the best database, as per its intent to use the data. Different databases are used for storing multiple varieties of data.1. Distributed DatabaseThis database is unlike a centralized database system, in which data is distributed among multiple DB systems of an organization. Communication links help in connecting these database systems.There are two categories of Distributed databases.Homogeneous DDB: The databases which carry the same hardware devices and use the same application process and are executed on the same operating system are known as Homogeneous DDB.Heterogeneous DDB: The databases which carry different hardware devices are executed on different operating systems under different application processes are known as Heterogeneous DDB.Distributed Databases help in modular development and if one server fails it will not cause the loss of the entire dataset. These are a few of the advantages of the Distributed Database.2. Relational DatabaseRelational data model is the main idea behind this database. In this database, data is stored in the form of rows and columns, which are together known as tables. SQL is the language that is used for storing, manipulating, and controlling data. A few of the examples of Relational databases are Oracle, MySQL, etc.There are four common properties of Relational Database which are ACID PROPERTIES. A stands for Atomicity, which means either the operation will fail or succeed. C stands for Consistency, which means before and after values of the transactions should be preserved. I stands for Isolation, which means data between concurrent users who are accessing the data at the same time should be isolated. D stands for Durability, which means that any changes in the data should remain permanent.It is one of the most mature databases, where every piece of information is related to every other piece of information. All data is tabulated in this model. Hence, each row is connected to another row using a primary key. In Relational databases, it is more convenient to traverse through the data. Therefore, they are quite light-weighted.3. Cloud DatabaseThis type of database stores the data in a virtual environment and is accessed over a cloud computing platform. There are various cloud computing services such as SaaS, PaaS, etc. It serves the main purpose as a traditional database but with the added flexibility of cloud computing. The software is installed on a cloud infrastructure to implement the database.Key Features:A database is accessed through a web interface or the API provided by the vendor.It can be managed by a user or can be provided as a service by the provider.It has made the work of enterprises easier by giving the service to host a database without actually rendering the services of hardware.4. Hierarchical DatabaseThis database stores data in the form of a parent-child relationship where the data is organized in a tree-like structure. Each child has a single parent but every parent can have multiple children. In this database, data is categorized based on a common point of linkage. Due to such a structure, hierarchical databases are not easily saleable as traversing through the data is quite tough in such an architecture.5. Network DatabaseThe representation of data in this database is in the form of nodes that are connected with links. It follows a network data model. The main advantage of a network database is that the pattern of the relationships among entities is quite natural, which is the opposite in a hierarchical model.6. Centralized DatabaseThis database stores the data at a centralized database system. Users are now able to access the data stored from multiple locations via different applications. It is a secure database that contains the authentication process for the users to securely access the data. Pros:Consistency of data is maintained as the data is managed in a chief repository.Standard of data quality is a bit higher.Risk of data management has been effectively decreased. Cons:Any glitch in the server will cause the entire data loss.Size of the database is large, which in turn increases the response time.7. NoSQL DatabaseThis database is used for storing a wide range of data sets. It does not follow a relational model and is not a relational database. Data here is stored in several ways. It caters to the need of modern applications. Since the developers can store a huge amount of unstructured data, this database is quite flexible.Key Features: It gives the provisions of Horizontal scaling.Developer-friendly database.All the schemas are quite flexible.The data model is such that queries execution is a tad faster.8. Object Oriented DatabaseWhen we apply object-oriented programming concepts on Relational data model, then it’s called Object Oriented database model. Data in these types of databases are stored in an object-based model approach and the data is stored in the form of objects.ConclusionIn conclusion, a database is efficient management to store and organize the data. Any database can be chosen depending on the needs and functionality, it caters to. Thus, a DB gives us a centralized facility to share the data among multiple users.