on 29 October 18
When you are developing a website, you may find the need to log the variables or the custom messages created for the website. While Magento 2 has a built-in log facility based on Monolog library, there will come a time when you need to create a custom log. You will find the default monolog along the path "MAGENTO2_ROOT/vendor/monolog"
The main log facility class defined for Magento 2 is "Magento\Framework\Logger\Monolog" which is defined along the path "MAGENTO2_ROOT/app/etc/di.xml" using the following code
The monolog/logger class has been extended to this class