KB article: OneDrive for Business information on limitations

OneDrive for Business works with Sharepoint or also called the Cloud or also known as O365. There are a set of limitations that are noted in KB article:

Restrictions and limitations when you sync SharePoint libraries to your computer through OneDrive for Business

https://support.microsoft.com/kb/2933738

In addition, there is specific Sharepoint Online (also known as Cloud or O365): 

SharePoint Online: software boundaries and limits

https://support.office.com/en-US/Article/SharePoint-Online-software-boundaries-and-limits-8f34ff47-b749-408b-abc0-b605e1f6d498?ui=en-US&rs=en-US&ad=US