JMS Messages and JMS Queue

Hello, I am new to the JAVA world and just wanted to get a better understanding of JMS Messages and JMS Queues.  There is plenty of documentation on the Internet describing these components but I really do not understand why you would need to use JMS Message.  

Let's say I have a process called "UpdateAllActiveAccountFlags".   This process runs every day at 5:00pm, updates a flag in a database and then writes to a log file.   In this case what would I use a JMS Message for and JMS Queue?  Is it for writing to a log file?