• Amazon Elastic Compute Cloud (Amazon EC2) is a web service that provides resizable compute capacity in the cloud.

• It is designed to make web-scale cloud computing easier for developers. Amazon EC2 enables you to increase or decrease capacity within minutes, not hours or days.

• The Amazon Elastic Compute Cloud (Amazon EC2) is a Web-based service that allows business subscribers to run application programs in the Amazon.com computing environment. The EC2 can serve as a practically unlimited set of virtual machines

Amazon S3 :

• Amazon S3's cloud-based storage system allows you to store data objects ranging in size from 1 byte upto 5GB in a flat namespace. In S3, storage containers are referred to as buckets, and buckets serve the function of a directory, although there is no object hierarchy to a bucket, and you save objects and not files to it.

• It is important that you do not associate the concept of a file system with S3, because files are not supported; only objects are stored,

• The S3 system allows you to assign a name to a bucket, but that name must be unique in the S3 namespace across all AWS customers. Access to an S3 bucket is through the S3 Web API (either with SOAP or REST) and is slow relative to a real-world disk storage system. S3's performance limits its use to non-operational functions such as data archiving and retrieval or disk backup.

• The REST API is preferred to the SOAP API, because it is easier to work with large binary objects with REST.

You can do the following with S3 buckets through the APIs:

1. Create, edit, or delete existing buckets

2. Upload new objects to a bucket and download them

3. Search for and find objects and buckets

4. Find metadata associate with objects and buckets

5. Specify where a bucket should be stored

6. Make buckets and objects available for public access

Amazon ESB :

• Amazon's data storage systems are devoted to Amazon Elastic Block Storage (EBS), which is a persistent storage service with a high operational performance.

• Advantages of EBS are that it can store file system information and its performance is higher and much more reliable than Amazon S3.That makes EBS valuable as an operational data storage medium for AWS. The cost of creating an EBS volume is also greater than creating a similarly sized S3 bucket.

• An EBS volume can be used as an instance boot partition. The advantages of an EBS boot partition are that you can have a volume up to 1TB, retain your boot partition separately from your EC2 instance, and use a boot partition volume as a means for bundling an AMI into a single package.

• EBS boot partitions can be stopped and started, and they offer fast AMI boot times. EBS is similar in concept to a Storage Area Network or SAN; you create block storage volumes varying in size from 1GB to 1TB and make those volumes available to your machine instances.

• The performance of a volume is dependent upon the network I/O and therefore varies as a function of the size of your instance, as well as the type of disk I/O operations (random, sequential, request size, and READS or WRITE) that are in progress.

Amazon Simple DB :

• Amazon SimpleDB is a highly available and flexible non-relational data store that offloads the work of database administration.

• Developers simply store and query data items via web services requests and Amazon SimpleDB does the rest. Unbound by the strict requirements of a relational database, Amazon SimpleDB is optimized to provide high availability and flexibility, with little or no administrative burden.

• Behind the scenes, Amazon SimpleDB creates and manages multiple geographically distributed replicas of your data automatically to enable high availability and data durability.

• The service charges you only for the resources actually consumed in storing your data and serving your requests.

• You can change your data model on the fly, and data is automatically indexed for you.

• With Amazon SimpleDB, you can focus on application development without worrying about infrastructure provisioning, high availability, software maintenance, schema and index management, or performance tuning.