Explain S3 and why is it used for?

Simple Storage Services or S3 is like ftp storage, where users can move files to and from there, but don’t mount it like a filesystem. SWS automatically puts the user snapshots as well as AMIs there. Encryption should be considered for sensitive data present in S3 as it’s a proprietary technology developed by Amazon and not yet proven with vis-a-vis a security standpoint.