The latest Prestashop version is 8.1.2. After version 1.7.x.x Prestashop dropped the "1" at the start. So instead of 1.8 you have 8. The marketing guys thought that was a good idea.
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The latest Prestashop version is 8.1.2. After version 1.7.x.x Prestashop dropped the "1" at the start. So instead of 1.8 you have 8.