What are the different between 3 type of the cron setup?

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1

Below code

*/1 * * * * php /var/wwwmagentroot/bin/magento cron:run [>> /log/file &]
*/1 * * * * php /var/wwwmagentroot/update/cron.php [>> /log/file &]
*/1 * * * * php /var/wwwmagentroot/bin/magento setup:cron:run [>> /log/file &

2

The first command (magento cron:run) reindexes indexers, send automated e-mails, generates the sitemap, and so on. Usually it’s associated with the PHP command line .ini file.
The other two commands are used by the Component Manager and System Upgrade.

If you’re a contributing developer (that is, you cloned the Magento 2 GitHub repository), only the first line applies to you.