You would filter a grid to restrict what records display for reporting, filter so that you can easily find data or filter to speed up the retrieval of data from the database.
For example you might filter on the Invoice Number column to only show workorders that have this field blank - so that you can see at a glance which workorders still need to be invoiced out.
•Filtering can be via one column or multiple columns in one grid.
•A clear 
on the column header indicates no filtering by this column is occurring.
•A colored 
on the column header indicates that filtering by this column is occurring.
•You will note that the Filter Drop List will show No Filter in the Filter Drop List if a filter is not set, or it is in the middle of a filter not yet saved or if you are presently viewing a previously saved filter
•Click on the object in the column heading to drop down a selection list of what to filter by. There are many choices depending on the type of data the column lists.
•You could select <ALL> to set no filtering, or depending on the type of data displaying in that column possibly [A – H] to display only data that begins with the letters A through H, and so on, or scroll further down to select a specific already displayed data to filter by.
•It is suggested that you try different scenarios till you get the results you need. You can always return to (ALL) or any other filtering easily.
See also:
How do I filter a grid and print a report for the records that show?
How do I create a custom filter?
Listing all workorders for a specific client
The last viewed filter(s), sort order, pinning and navigation pane grid showing when you as an AyaNova user exited out will be the filter and navigation pane grid showing when you next log in.
For example, if you are a schedulable user, you may always want to initially view the Scheduled Users grid but filtered by your owned name to only show workorder items where you are scheduled.
If the username you use is used by multiple users, do note that if that username is logged in multiple times, any filtering you set may be overwritten by others also logged in under that same username.
For this reason, it is recommended to have every user log in under an individual username.