What is the difference between "Hidden Web Part" and "Closed Web Pat"?
I tried to search on the internet but could only find "deleting vs. closing" web parts
Sharepoint 2010 (Sharepoint Designer 2010)
Update (due to one of confusing answers to this question):
The quote from [1. p.119]:
Tip Closed Web Parts can increase the time it takes for a browser to load the page. Keep the number of closed Web Parts to a minimum and only close a Web Part when you want to temporarily hide a Web Part and its customizations. In the browser, you can find closed Web Parts by first placing a page in edit mode. Then, on the Editing Tools, Insert tab on the server ribbon, click Web Part, and under Categories, click Closed Web Parts. The Closed Web Parts category appears only if the page contains closed Web Parts.
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