Upgrade magento 2 to latest version
Note : Before running upgrade should have to take database and file backup.
To upgrade magento 2 from UI you have to follow below mentioned document.
To upgrade magento 2 with composer or command line or SSH use below mentioned command.
First of all you you need to update composer.
After that check magento version if version is still same use below mentioned command.
You have to update magento installer first so apply below mentioned command.
composer require magento/magento-composer-installer composer require magento/product-community-edition '2.0.*' --no-update
Now you have to run composer update command so it will upgrade php dependency and latest magento packages.
Now after done with upgrading all magento and php packages you have to run run below command to make sure that all database base updates are done.
php bin/magento setup:upgrade
Enjoy your magento 2 should upgraded in latest magento version.