There are many links that I find myself going to over and over again for different elements of Office 365 and Azure
For details of the developments that are in progress and being rolled out
URLs and IPs
Any client that needs Office 365 will ask sooner or later what they need to do to allow, or in some cases block, access.
Often, when dealing firewalls expect an IP range when opening access and the CIDR format that Microsoft provides isn’t compatible. If this is the case, then a tool such as http://www.ipaddressguide.com/cidr can be perfect for converting CIDR to IP address ranges.
Office 365 Search
SharePoint Search REST API overview - https://msdn.microsoft.com/en-us/library/office/jj163876.aspx
Query Refinement in SharePoint 2013 - https://msdn.microsoft.com/en-us/library/office/ff394639.aspx