Are Fiscal calendars and Accounting calendars the same in crm?

Summary:

Similarity between Fiscal calendars and Accounting calendars the same in CRM.

Content (please ensure you mask any confidential information):

Basically the query here is that if the Fiscal calendar and accounting calendar same or if there is a separate configuration for both of them (i.e. if they are different)

1. If yes, then how can we set up fiscal calendar and use it as filter on sales dashboard time filter?
2. If both are same, then why fiscal quarter filters are not supported on sales dashboard.?

Version (include the version you are using, if applicable):

25B

Code Snippet (add any code snippets that support your topic, if applicable):