CSV:
With CSV format you will be able to export your issues and import them into another Jira instance. You can choose the delimiter, select between Comma, Semicolon, Vertical bar or Caret.
Tips for using CSV Export
Backup your issue data: You could use the CSV Export as backup maker. You may use .CSV exported files to recover or review the issue data.
Export your issues to other management applications: CSV data is a standard and a long-used model to transfer data between applications. That way, you can export your Jira issues and import them onto others management system. Just as easy as you need.
Analyze your issue data with external applications: You are able to use other external applications to analyze some metrics of your Jira issues. CSV exported file will give you all the data you need to analyze making this process more agile.