Types of document storage in SalesForce:
| Feature/ Type | CRM Content | Files tab | Documents tab | Notes and Attachments related list | Google Docs tab |
| Can associate with a record | Yes, through content types/workspaces /lookup fields | No | No | Yes, mandatory | No |
| File size limit | ? 500 Mb/user | 100 Mb/file | 5 Mb/file | 5 Mb/file, 10 Mb/email | 1 Gb/file upgradeable |
| Can be imported through Data Loader | Yes | No | Yes | Yes | No |
| Externally accessible through link | Allowed | Allowed | Allowed for images only | No | Yes |
| Can see files from other tabs | No | Yes | No | No | No |
| Tracks when file is viewed | Yes | No | No | No | No |
| Search inside the file | Yes | Yes | Yes | No | No |
| View file in web page | Yes | Yes | No | No | Yes |
| Mobile access | Yes | ? | No | No | ? |
| Can create content packages | Yes | Yes | No | No | No |
| Can follow/ be notified of file updates | Yes | Yes | No | No | No |
| Private section | Only if file is on personal workspace | Yes | Yes | No | No |
| Relation to Chatter | Yes | Yes | No | ? | No |
Pertinent discussions:
What’s the actual difference between the Documents, Content and Files tab?
What is the difference between a Chatter file and a Salesforce CRM Content file?
Viewing and Editing Google Docs, Notes, and Attachments
What is the CRM Content file size limit?
SF App Limits Cheatsheet
Differences between Files, Salesforce CRM Content, Salesforce Knowledge, Documents, and Attachments
Please let me know if you find any inaccuracies in the table above.