Cloud Storage: Block, File, and Object Storage Explained

You want to store something in the cloud, and suddenly you’re faced with three terms that all seem to mean the same thing: block storage, file storage, and object storage. It might sound like splitting hairs, but this decision will ultimately determine whether your database runs smoothly, your backups remain affordable, or your team can access shared files without any issues. Not all cloud storage is created equal. These three types of storage work in fundamentally different ways and are designed for different tasks.

In this article, we’ll explain the differences between block, file, and object storage, what each is used for, and how to choose the right option for your project. No technical jargon—just concrete examples.

The Three Types of Storage at a Glance

In short: Block storage divides data into blocks of equal size and is suitable for fast-changing data, such as databases. File storage organizes data into a folder and file structure and is ideal for shared access. Object storage stores data as objects along with metadata and scales virtually indefinitely, making it suitable for backups, archives, and media.

Why are there three approaches in the first place? Because data has very different requirements. A database needs low latency and fast random access. A shared project directory needs a familiar folder structure that multiple people can access at the same time. And a photo archive with millions of files needs one thing above all else: cost-effective scalability. Each type of storage solves exactly one of these problems particularly well. Let’s take a look at them one by one.

Block Storage: Storage Like a Hard Drive

Block storage is the type of storage that feels most like a traditional hard drive. That is exactly why it is so widely used in cloud environments.

How Block Storage Works

With block storage, your data is divided into many units of equal size, known as blocks. Each block is assigned a unique address, but no additional information about its contents. The system simply keeps track of where each block is located and reassembles the blocks as needed.

The key feature is random access: The system can directly access and modify a single block without having to access the entire file. That’s exactly what makes block storage so fast for data that’s constantly changing. In the cloud, this storage is usually provided as a standalone volume that you attach to a virtual machine, just like you would attach an external hard drive to your laptop.

What you use it for

Block storage is the top choice when speed and frequent changes are key. Typical use cases include databases such as PostgreSQL or MySQL, the system drives of virtual machines, and applications with many small read and write operations.

In short: Whenever a service acts as if it has a local hard drive, you’re using block storage. The trade-off for this performance is limited flexibility, since a volume is typically tied to a single instance and cannot be easily shared among multiple systems at the same time.

Advantages of Block Storage

• Speed: When all blocks are stored locally or in close proximity to one another, block storage offers high performance with low latency when retrieving data, which is why it is often used for business-critical data.
• Reliability: Since blocks are stored as independent units, block storage has a low failure rate and supports data replication for increased reliability.
• Simple edit: To edit a block, you don’t need to create a new one. Instead, you can create a new version.

Limitations of Block Storage

• Lack of metadata: Block storage does not contain metadata, making it less suitable for storing unstructured data.
• Limited searchability: Large amounts of block data quickly become unmanageable due to limited search functions.
• High costs: Purchasing additional block storage is expensive and often unaffordable when very large amounts are involved.

Use Cases for Block Storage

• Databases: Because of its high performance and support for seamless update operations, block storage is used by many companies to store data in transactional databases.
• Enterprise Applications: Business-critical applications such as ERP, CRM, and financial systems rely on block storage to ensure consistent performance and data integrity.
• High-Performance Applications: Business-critical applications that require consistent storage performance with low latency rely on block storage to ensure an optimal user experience.
• Persistent Container Volumes: Modern containerized applications use block storage to ensure data persistence throughout the entire lifecycle of containers and within automated container orchestration platforms such as Kubernetes.

File Storage: The Shared File Repository

File storage is what most people intuitively think of as storage: files are stored in folders, folders are stored in folders, and everything has a traceable path.

How File Storage Works

In file storage, data is organized into a hierarchical structure of directories and files. Access is via a path, such as /projects/2026/quote.pdf. You’re familiar with this structure from every file server and every network drive in the office.

Technically, file storage in the cloud is often provided via network protocols such as NFS or SMB. The big advantage is that multiple systems and users can access the same storage at the same time and share files without you having to worry about blocks or objects.

Typical application scenarios

File storage really shines whenever people or applications need to access the same set of data together. Classic examples include shared project directories, content management systems with shared media folders, and legacy applications that simply expect a file system and are not intended to be rewritten.

This type of structure is also ideal for team collaboration and file storage. Anyone looking to collaborate in a way that’s both data-privacy compliant and well-organized will find that a solution like Nextcloud offers exactly this familiar folder structure—only as a managed service rather than a server in the basement.

Benefits of File Storage

• Easy Navigation: When there are a small to moderate number of files, users can easily find and access target files using familiar folder structures.
• Intuitive for most users: As the most common type of storage for end users, people with basic computer skills can easily use file storage with minimal learning effort.
• Direct User Control: Through a simple user interface, end users can create, move, and delete their own files without needing administrative assistance.
• Granular access control: Users and administrators can set files to be writable, read-only, or password-protected to ensure secure file sharing.

File Storage Limits

• Difficult-to-scale management: File management becomes increasingly complicated as folder structures grow in size, leading to slower searches and lower productivity across the entire company.
• Not well-suited for unstructured data: While it is possible to store unstructured data such as text, mobile activity, social media posts, and IoT sensor data in file storage, this is not ideal for storing large volumes of data.

Use Cases for File Storage

• Document Collaboration: File storage enables teams to work together on shared documents through centralized access. Modern cloud-based file storage systems such as Nextcloud feature built-in version control and real-time collaboration capabilities that manage simultaneous edits and save document history.
• Backup and Recovery: Cloud backups and external backup devices typically use file storage to create copies of the latest versions of files.
• Archiving: Because file storage allows organizations to set permissions for sensitive data at the file level and is easy to manage, many companies use it to archive documents for compliance or historical reasons.

Object Storage: Built for Large Amounts of Data

Object storage is the newest of the three approaches and the answer to a question that hardly anyone asked 20 years ago: How do I store hundreds of millions of files without losing control of the structure and costs?

How Object Storage Works

Object storage does away with the folder hierarchy. Each file is stored as a standalone object, along with a unique ID and extensive metadata. Instead of being organized in a nested directory tree, all objects are stored in a flat namespace called a “bucket.”

Access is not via a file path, but through an API—usually the widely used S3 API. It is precisely this flat structure that makes object storage so unbeatably scalable. Whether you store a thousand or a billion objects makes no structural difference to the system. The metadata helps you locate and manage specific objects later on.

What it’s for

Object storage is the right choice for large volumes of unstructured data that are written once and then primarily read. This includes backups and archives, images, videos, and other media, static assets for websites, as well as data for analytics and data lakes.

Another advantage is the price: Object storage is generally much cheaper per gigabyte than block storage. However, it is not intended for data that changes constantly in small increments, since an object is always written as a whole. If you’re looking for flexible, instantly available storage for growing data volumes, S3 Object Storage from NETWAYS Cloud Services is the right solution for you.

Benefits of Object Storage

• Processes large volumes of unstructured data: Object storage systems store and manage this data efficiently, which is crucial for workloads related to artificial intelligence (AI), machine learning (ML), and big data analytics.
• Cost-Effective Usage Model: Object storage ensures cost efficiency. Instead of paying in advance for a specific amount of storage—as is typical with file storage—you only purchase the object storage you actually need, on demand.
• Unlimited scalability and high reliability: Thanks to the usage-based model, you can add as much additional storage as you need, ensuring a scalable solution. At the same time, built-in redundancy and data protection mechanisms ensure high reliability and protect your data over the long term.
• Comprehensive metadata capabilities: Metadata is stored along with the objects, allowing users to quickly derive value from the data and more easily locate the objects they need.
• Advanced Search Capabilities: Object storage allows users to search metadata, object content, and other properties.

Limitations on Object Storage

• Limited File Locking: Object storage does not have traditional file locking mechanisms, although modern services offer object-level retention and version controls that function differently from file system locks.
• Higher latency compared to other types of storage: Object storage has traditionally had higher latency than block storage for transactional workloads, although modern implementations have improved performance for many use cases.
• Limitations on editing individual parts of a file: Once an object has been created, it can no longer be edited in place. Instead, you create a new version, although modern services offer version control features to apply updates effectively.

Use Cases for Object Storage

• Email Archiving and Compliance: Companies use object storage for the long-term retention of emails, archiving to comply with legal requirements, and backing up cloud-based email systems.
• Backup/Disaster Recovery: Object storage is often used for backup and disaster recovery, where performance requirements are lower.
• Video Surveillance: Object storage offers a cost-effective solution for large-scale video storage and long-term retention of footage.
• AI/ML Training Data: Thanks to its built-in scalability and metadata capabilities, object storage is ideal for storing large datasets used in training machine learning models and in AI applications.
• Real-time analytics: Companies use object storage to store streaming data and logs, which are fed into analytics platforms to gain business intelligence and operational insights.

Which Storage Option Is Right for You? A Direct Comparison

To help you quickly compare the three types, here are their key features side by side:

Criterion	Block Storage	File Storage	Object Storage
Structure	Blocks with Addresses	Folders and Files	Objects with Metadata
Access	Per volume per instance	via file path (NFS/SMB)	via API (e.g., S3)
Latency	very low	low to medium	medium
Scaling	limited	medium	virtually unlimited
Cost per GB	higher	medium	low
Ideal for	Databases, VMs	Shared directories, legacy apps	Backups, Media, Archives

As a rule of thumb, keep the following in mind: If your service needs a fast, scalable hard drive, go with block storage. If multiple users or systems need to share shared folders, file storage is the right choice. And when it comes to massive amounts of files that need to scale cost-effectively, there’s really no way around object storage.

In practice, you often combine these types. A typical use case involves using block storage for the database, object storage for backups and media, and perhaps file storage for a shared workspace. The trick isn’t to pick a winner, but to assign the right type of storage to each task.

Common Mistakes When Choosing Cloud Storage

Many companies choose their storage solution based solely on price.

In doing so, important factors are overlooked:

• Performance Requirements
• Number of concurrent connections
• Scalability
• Data Security
• Backup Strategy
• Compliance Requirements
• Integration Options

Choosing the wrong type of storage can result in high costs later on or significantly impair application performance.

Best Practices for Businesses

Before selecting a storage solution, companies should answer the following questions:

• Which applications access the data?
• What is the expected rate of data growth?
• How many users need simultaneous access?
• Are APIs needed?
• What level of performance is required?
• Are there any legal requirements regarding data storage and privacy?
• What backup and disaster recovery strategy is being followed?

In many cases, a combination of different types of storage is the most sensible solution.

Conclusion

Block, file, and object storage are not competitors, but rather tools for different tasks. Block storage excels in speed when handling changing data, file storage offers a familiar structure for shared access, and object storage provides cost-effective, virtually unlimited scalability. Choosing the right type of cloud storage from the start saves you from costly retrofits and frustrating performance issues down the road. Ultimately, what matters isn’t which storage solution is the most advanced, but which one best fits your specific use case.

You don’t have to make this decision on your own. If you’re unsure which combination is right for your setup, a personal contact can often help you more quickly than any white paper.

What type of storage do you currently use most often, and does it really suit your data needs? Feel free to let us know in the comments. And if you want to set up your cloud storage flexibly in a German data center, take a look at our Cloud Services.