When creating scripts you can use the system variable [$_User Name] to get the name of the user who has called the script.

For example, if we want to log the changes of database records, we can apply the Apply Text Formula to a field action for the on change event of a text field. The parameters will be the following:

In this case, when the text box is modified, the following information will be added in the log field:

2006-06-23 12:01:45 John
2006-06-23 15:45:10 Tom
2006-07-02 13:02:34 Mary

In this example John, Tom and Mary are names of users who modified this record.

To learn more, see the Scripts and Text Formulas sections.