What Is Data Classification? Types and Identifiers

Data Discovery

What is Data Classification?

Data classification is all about understanding and organizing data into defined categories and types that are relevant to a specific organization.

Classifying data by sensitivity, policy, or other attribute enables organizations to identify, organize, protect, manage, and report on data throughout its lifecycle to meet regulatory compliance and other business needs.

Purpose of Data Classification

Data classification has multiple applications — and is critical to privacy, risk mitigation, security, governance, discovery, and compliance initiatives.

With the right technology and automated classification techniques, companies can find and understand all of their data, know where it is located, identify its contents — and ultimately make better decisions around it. Those decisions may affect privacy, security, governance — or all of the above. Regardless of its application, effective data classification is a necessary starting point.

Data classification enables users — without opening or changing any file itself — to determine if the data contains sensitive, critical, personal, confidential, restricted, or otherwise regulated information. This helps organizations answer important questions like:

  • where all of their data is stored
  • where their most sensitive data resides
  • what their data contains
  • whose data it is

Data Classification Vs. Data Categorization

While data classification and data categorization are sometimes used synonymously, they are not the same. Data categorization is the ability to recognize shared features or similarities between data so that it can then be classified, simplified, and understood.


The process of analyzing structured and unstructured data and organizing it into predefined categories based on file type, content, and other metadata.


The process of recognizing shared characteristics or features among data so users can define groups and assign tags or names to identify appropriately.

Why is Data Classification Important?

Organizations can’t monitor and control what they don’t know about — or can’t find.  You can’t protect your most sensitive data from theft if you don’t know where it resides. You can’t determine which types of data should remain on-prem versus which you should move to the cloud if you don’t know what the data contains. You can’t effectively respond to DSARs if you can’t determine who your data belongs to.

To optimize security and reduce costs around security efforts, effective classification can determine which data is your most valuable data so you can prioritize its protection. Meanwhile, you can allow less valuable data to live in a less monitored, more affordable environment.

Requirements of Data Classification

Data classification and labeling is a necessary step toward building any governance, information security, or privacy program — and it is a prerequisite for meeting regulatory compliance for GDPR, CCPA, HIPAA, or just about any local, global, federal, or state compliance standard.

While some regulations require that organizations maintain certain categories for classified data (e.g., SOC2 requires a category for “confidential” data and GDPR specifies labels such as “public,” “proprietary,” “confidential,” and even “special”), not all regulations require specific categories — and this is not consistent from one to another.

Many organizations that focus on regulatory compliance begin with some variation of the following categories:

  • Public data: Data published on a publicly facing channel, freely available and accessible for use, reuse, and redistribution.
  • Private / Internal data: Data — often proprietary to a business — that is not meant for public disclosure.
  • Confidential data: Data that may be subject to regulations and may require specific authorization and clearance to access — often includes sensitive data.
  • Restricted data: Data that is highly sensitive and could put an organization at risk.

Types of Data Classification

There are multiple ways in which organizations can classify their data, but all these ultimately fall under two main models: manual and automated classification.

Manual classification requires training data owners to classify all of a company’s data by category or label. Manual processes are not only very expensive and time-consuming, but they are impossible to scale to the exponential growth of data types, sources, and regulations.

Furthermore, like any repetitive task performed by humans, manual classification is prone to errors, leading to incomplete or incorrect classification.

Automated classification delivers effective results with less cost and less effort. Automated processes use trainable, deep-learning models that can scale and look everywhere into all of your structured and unstructured data, at rest and in motion. This allows you to apply data classification rules consistently and dynamically as the data moves across its lifecycle.

Data Classification Use Case

BigID approaches data classification differently. It embraces a discovery in-depth approach that goes deep and wide: finding data wherever it is and layering in context and correlation for classification.

BigID’s classification approach extends and enhances traditional classification methods while also expanding coverage over multiple types of sensitive information — from personally identifiable information to profile information to broader sensitive information.
For example, a particular large retailer uses BigID to classify and identify where sensitive and critical data resides in their organization — and how to protect it.

The company has been using BigID for a global initiative to discover and classify sensitive, critical, and personal data across all of their 1,200+ data sources — and for more than 73,000 employees. With a unified inventory of their data, the customer has started broader governance initiatives.

How to Classify Data with BigID

BigID provides four types of data classification, all purpose-built for today’s data environment, volume, variety, and regulatory landscape.

data classification framework

Regular Expression and Pattern Matching

The traditional, pattern-based classification relies on regular expressions and patterns to find exact matches in strings of data. BigID has modernized this approach and added security identifiers. For instance, organizations can identify security-focused data points like API keys, credentials, tokens, and even common passwords.

Contextual Classification

BigID leverages Machine Learning (ML) and Named Entity Recognition (NER) to automatically identify sensitive information and link that specific instance of sensitive information into an individual identity or profile.

File Classifier by Type

Machine-learning models automatically classify documents based on the content and structure of a file — without being limited to any specific data classifier. These models can recognize sensitive file types like financial statements or boarding passes.

Policy-based Classification

BigID has built-in policy libraries to help classify, manage, and protect specific types of data by policy. This enables organizations to build workflows across specific types of data, manage access, monitor use, and protect sensitive data that may be under attack.

Guidelines for Data Classification

Data classification creates a huge chunk of the bedrock of any data privacy, security, and governance initiative — and it must therefore be a high priority for organizations that want to protect their sensitive data and maintain regulatory compliance.

To properly manage and secure valuable data, firms need to know their data, understand their data, and be able to easily answer: what it is, where it is, and who it belongs to.

BigID provides a powerful, intuitive platform and highly effective, easy-to-use data classification that leverages machine learning. Organizations can quickly and automatically identify sensitive and critical data across hundreds of data sources and build tailored data governance strategies to manage, monitor, and protect all their data.

Schedule a demo to learn more about how BigID can help you to know your data with ML-based classification.