In Dynamics 365 Business Central, the 'work date' is a system-wide date setting that allows users to specify a date different from the current calendar date for various operations and transactions. Here's a brief explanation of what it is and why you might want to change it: What is the work date:

1. It's a user-specific date setting that can be different from the actual calendar date.
2. It serves as the default date for new documents, journals, and transactions.
3. The work date is displayed prominently in the Business Central interface when it differs from the current date.

Why you might want to change it:

1. Backdating transactions: To enter transactions for a previous date without changing the posting date on each entry.
2. Month-end processing: Set the work date to the last day of the month to easily process end-of-month transactions.
3. Future planning: Set a future date for planning or forecasting purposes.
4. Consistency in batch processing: Ensure all entries in a batch have the same date without manually entering it each time.
5. Testing and simulations: Use a specific date for testing scenarios or simulating business processes.
6. Auditing and reviewing: Easily review or work with historical data by setting the work date to a past period.

 Here is a quick video on how to change it: