In simple words, it asking what you have done in your previous job?
Try to cover the below points while giving answer to this question:-

1. Interacting with client on requirement if any.
2. Coding and Development.
3. Support and bug fixing if any.
4. Code review and provide comments if any.
5. Your key contribution towards the projects that you are working. Don’t explain your project details just your key contribution.

Finally your achievement’s in the project and to the company if any.

dont give one line answer . describe something details like about your position details, work details and your contribution to the project etc