What is SharePoint?

[ffox]

It is very human-friendly & easy to understand.

Absolutely. A simple tutorial is all that is needed to enable a user to store and retrieve files in SharePoint. It takes little more to enable a user to create bespoke libraries for file storage.

This is a best tool to store or kept records safe.

Yes. SharePoint stores files in a SQL database. Retrieval and security are second to none, and that includes local machine and network storage.

We can say that it is a replacement of Dropbox

No. SharePoint should never be compared to Dropbox, Google Apps, Google Docs, Amazon cloud offerings or Microsoft OneDrive Live. These are good products and competitive in the market place they serve, but they are just cloud storage. They all store files off-site in an NTFS type file store. SharePoint on-line stores files in a SQL database delivering huge advantages in security, file grouping, file analysis and file location.