Please provide more detail, what do you mean by copying the data from table? Where you want to copy? Do you want to export the table rows? to csv file?
You can view this thread How To Directly Export ARS Tables to CSV (version 2)
There are multiple ways to copy/export data, it depends on your explanation in detail.
When I select a row (multiple rows) in a table want to copy the content and paste in word file/Notepad/outlook etc.
Not as spread sheet.
I thought of creating a character field. And on selection of row, populate the data in that field on click of button (AL). But I am looking for a cleaner approach (basic copy/paste that is user friendly)
You need to create the report (AR system report) add button to launch the report and then copy to where ever you want to paste.
Just for example look at the Incident form work log detail tab. (3rd button from left)
These are the ALs associated with this button.
These ALs call build qualification on selected row and pass to report to display these records, where you can copy.
That is interesting approach.
User still need to click on a button and then copy the data from another tab (Report).
I was also thinking to have workaround make column editable and then copy from there table itself. But limitation there is can copy only sell based, Can't select multiple cells (rows).
You can also use the JS to copy the table contents to clipboard and paste where you need it.
All options are there, which approach suites your users and your technical skills and comfort level to implement.