What is stateful and stateless in Salesforce?

<div>If your batch process needs information that is shared across transactions, one approach is to make the Batch Apex class itself stateful by implementing the Stateful interface.

</div><div>Batch Apex is stateless by default. That means for each execution of your execute method, you receive a fresh copy of your object. All fields of the class are initialized, static and instance.

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