The database (DB) is intended for storage of various kinds of information (about clients, goods, orders, etc.). Each of us in our lives meets with the need to store some records: contact details, addresses. Someone writes them in pads - this is a peculiar database.

   There are different types of them. Let's consider their basic classification.

   Depending on the nature of the data:

• factual - contain information about objects and processes presented in a specific format;
• documentary - include information of various types (graphic, textual, etc.).

   By way of data submission:

• hierarchical - has a so-called tree-like image (one element main, and all others are subject);
• relational - the data associated with each other, stored in a table;
• network - include objects of different levels that can be linked with each other.

   There are several stages of DB development:

• formation and substantiation of the purposes of the database creating;
• definition of tables and their structure;
• choice of model for database creation;
• download the necessary data;
• creation of queries, modules, forms, etc.

   At present, technologies are developing rapidly and can greatly simplify life. That is why, in order to be able to store large volumes of information, programmers have developed a so-called database management system (DBMS). It can be said that it is an intermediary between the database and users.

   The main advantages of the DBMS are:

• data protection;
• quick information search;
• high reliability and availability;
• control over the data;
• backup.

   Here are the most commonly used database management systems:

• MS Access - contains tools that are designed to create relational databases based on relational data models. The main elements are tables, reports, macros, queries, modules, and forms;
• MySQL - used to format databases of adding and processing) of different scales;
• Oracle - is a software product whose main functions consist in data management, storage and protection;
• PostgreSQL - a system designed to add and process data;
• MS Excel - has a wide range of users, used to work with data tables;
• SQLite - supports various types of data, including null, text, blob, real, and others. The main advantage is the storage of the database in one file;
• Firebird SQL - is free open source software for which you don`t need to register. Its main advantages are: small size of the installation package, compatibility with the most commonly used operating systems, backups, etc.

   By using the DBMS, the user is able to:

• develop a database structure;
• to fill the DB by information and edit it;
• do a data search.

   You must understand that choosing of a data model and database management system - is a serious matter. Therefore, all important criteria should be considered: reliability, speed, availability of detailed documentation, architecture, frequent use by other users, enterprise policy, and, of course, financial capacity.