Content: Difference between Synchronous and Asynchronous in Salesforce
In simple terms you can assume Synchronous as Sequential. In Synchronous process the thread waits for the task to be completed and then moves to the next task Sequentially. All the tasks are completed in a single thread.
The common example of a Synchronous apex is.
In Asynchronous apex the thread does not waits for the task to be completed to move on to the next task. The tasks are run in different threads all together. These threads run in independent silos whenever the system is free.
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