The main window's context menu has Copy Column Text from Selected Rows and Paste to Column in Selected Rows items. These items always work with the column which was clicked to display the context menu. A newline character is used as the line delimiter when copying and pasting.
You can copy the text of most columns. However you can only use the paste functionality on columns which are editable. When pasting text from the clipboard, the clipboard must contain the same number of rows as are selected in the main window.
You can also copy the data is the clicked row to all other selected rows. Use the Copy Cell to Same Column in Selected Rows context menu item.