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@@ -537,8 +537,8 @@ S3
 -	Items, or **objects**, are placed into named **buckets** stored with names which are usually called **keys**. The main content is the **value**.
 -	Objects are created, deleted, or updated. Large objects can be streamed, but you cannot access or modify parts of a value; you need to update the whole object.
 -	Every object also has [**metadata**](https://docs.aws.amazon.com/AmazonS3/latest/dev/UsingMetadata.html), which includes arbitrary key-value pairs, and is used in a way similar to HTTP headers. Some metadata is system-defined, some are significant when serving HTTP content from buckets or CloudFront, and you can also define arbitrary metadata for your own use.
--	Although often bucket and key names are provided in APIs individually, it’s also common practice to write an S3 location in the form 's3://bucket-name/path/to/key' (where the key here is 'path/to/key'). (You’ll also see 's3n://' and 's3a://' prefixes [in Hadoop systems](https://wiki.apache.org/hadoop/AmazonS3).)
--	AWS offers many storage services, and several besides S3 offer file-type abstractions. [Glacier](#glacier) is for cheaper and infrequently accessed archival storage. [EBS](#ebs), unlike S3, allows random access to file contents via a traditional filesystem, but can only be attached to one EC2 instance at a time.
+-	**S3 URIs:** Although often bucket and key names are provided in APIs individually, it’s also common practice to write an S3 location in the form 's3://bucket-name/path/to/key' (where the key here is 'path/to/key'). (You’ll also see 's3n://' and 's3a://' prefixes [in Hadoop systems](https://wiki.apache.org/hadoop/AmazonS3).)
+-	**S3 vs Glacier, EBS, and EFS:** AWS offers many storage services, and several besides S3 offer file-type abstractions. [Glacier](#glacier) is for cheaper and infrequently accessed archival storage. [EBS](#ebs), unlike S3, allows random access to file contents via a traditional filesystem, but can only be attached to one EC2 instance at a time. [EFS](#efs) is a network filesystem many instances can connect to, but at higher cost. See the [comparison table](#storage-durability-availability-and-price).
 
 ### S3 Tips