Data access is a generic term referring to a process which has both an IT-specific meaning and other connotations involving access rights in a broader legal and/or political sense. Two fundamental categories of data access exist:

• sequential access (as in magnetic tape, for example)
• random access (as in indexed media)

The sequential method requires information to be moved within the disk using a seek operation until the data is located. Each segment of data has to be read one after another until the requested data is found. Reading data randomly allows users to store or retrieve data anywhere on the disk, and the data is accessed in constant time.

Oftentimes when using random access, the data is split into multiple parts or pieces and located anywhere randomly on a disk. Sequential files are usually faster to load and retrieve because they require fewer seek operations.

Access data management crucially involves authorization to access different data repositories. Data access solutions can help distinguish the abilities of administrators and users. For example, administrators may have the ability to remove, edit and add data, while general users may not even have "read" rights if they lack access to particular information.

A data access right (DAR) is a permission that has been granted that allows a person or computer program to locate and read digital information at rest. Digital access rights play and important role in information security and compliance.

In compliance, DARs are often granted to data subjects by law. For example, under the General Data Protection Regulation (GDPR) in the European Union, a data subject has the right to access their own personal data and request a correction or erasure.

To avoid losing or corrupting corporate data, organizations should grant only the necessary required access to each user, a concept known as the principle of least privilege (POLP). To ensure confidentiality, information should be used by authorized personnel only. To maintain data integrity, data should not be modified accidentally or voluntarily. Additionally, to provide data availability, the system should operate within the required levels of service.

Historically, each repository (including each different database, file system, etc.), might require the use of different methods and languages, and many of these repositories stored their content in different and incompatible formats.

Over the years standardized languages, methods, and formats, have developed to serve as interfaces between the often proprietary, and always idiosyncratic, specific languages and methods. Such standards include SQL (1974- ), ODBC (ca 1990- ), JDBC, XQJ, ADO.NET, XML, XQuery, XPath (1999- ), and Web Services.

Some of these standards enable translation of data from unstructured (such as HTML or free-text files) to structured (such as XML or SQL). Structures such as connection strings and DBURLs can attempt to standardise methods of connecting to databases.