There are 6 types of EBS volume types

gp2/gp3 (SSD) – General Purpose SSD good blances of price and performance.

                1.  Can be used as boot volumes

                2.  Cost effective

                3.  1GiB to 16TiB

                4.  gp3 3000 IOPS and 125MiB/s base

                5.  gp3 16000 IOPS and 1000MiB/s max

                6.  gp2 older with less performance

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io1/io2 Block Express (SSD) – Highest performance SSD volume for mission critical.

                1.  Can be used as boot volumes

                2.  Critical system

                3.  databases would be a good use of these volumes

                4.  io1 4GiB – 16TiB  PIOPS to 64000

                5.  i02 4GiB – 64TiB PIOPS to 256000

                6.  Support EBS multi-attached feature

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St1 (HDD) – Low cost HDD for frequently accessed and high throughput.

                1.  Cannot be used as boot volumes

                2.  125GiB to 16TiB

                3.  Data Warehousing, batch processing.

                4.  500 IOPS and 500MiB/s base

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Sc1 (HDD) – Lowest cost HDD designed for less accessed data.

                1.  Cannot be used as boot volumes

                2.  125GiB to 16TiB

                3.  Data Warehousing, batch processing.

                4.  500 IOPS and 500MiB/s base

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