Introduction

Azure Blob storage is Microsoft's object storage solution for the cloud.
Blob storage is optimized for storing massive amounts of unstructured data.
Blob storage is designed for:
- Serving images or documents directly to a browser.
- Storing files for distributed access.
- Streaming video and audio.
- Writing to log files.
- Storing data for backup and restore, disaster recovery, and archiving.
- Storing data for analysis by an on-premises or Azure-hosted service.
Users or client applications can access objects in Blob storage via HTTP/HTTPS, from anywhere in the world.
Objects in Blob storage are accessible via the Azure Storage REST API, Azure PowerShell, Azure CLI, or an Azure Storage client library.
An Azure Storage account is the top-level container for all of your Azure Blob storage. The storage account provides a unique namespace for your Azure Storage data.

Types of storage accounts

Azure Storage offers two performance levels of storage accounts, standard and premium. Each performance level supports different features and has its own pricing model.
Standard: :
- This is the standard general-purpose v2 account and is recommended for most scenarios using Azure Storage.
- Standard storage account type for blobs, file shares, queues, and tables.
Premium:: Premium accounts offer higher performance by using solid-state drives. If you create a premium account you can choose between three account types, block blobs, page blobs, or file shares.
- Premium storage account type for block blobs and append blobs. Recommended for scenarios with high transaction rates or that use smaller objects or require consistently low storage latency
- Page blobs: Premium storage account type for page blobs only.

Azure Storage provides different options for accessing block blob data based on usage patterns.
Each access tier in Azure Storage is optimized for a particular pattern of data usage.
By selecting the right access tier for your needs, you can store your block blob data in the most cost-effective manner.
The available access tiers are:
- Hot access tier:
  - Optimized for frequent access of objects in the storage account.
  - Hot tier has the highest storage costs, but the lowest access costs.
  - New storage accounts are created in the hot tier by default.
- Cool access tier:
  - Optimized for storing large amounts of data that is infrequently accessed and stored for at least 30 days.
  - The Cool tier has lower storage costs and higher access costs compared to the Hot tier.
- Cold access tier:
  - Optimized for storing data that is infrequently accessed and stored for a minimum of 90 days.
  - Cold tier has lower storage costs and higher access costs compared to the cool tier.
- Archive tier:
  - Optimized for data that can tolerate several hours of retrieval latency and remains in the Archive tier for at least 180 days.
  - The archive tier is the most cost-effective option for storing data, but accessing that data is more expensive than accessing data in the hot or cool tiers.
If there's a change in the usage pattern of your data, you can switch between these access tiers at any time.