In the previous chapter, we saw how to perform all the DynamoDB operations using the REST API. We also discussed in detail each and every JSON request used and its response, and understood that even a simple browser is more powerful in the hands of an intelligent programmer. DynamoDB is a distributed and redundant database, which means two things. The first thing is that every large set of table data will be distributed among multiple servers, and the second thing is that every item (copy of the data) will be made available on multiple servers so that even if one server becomes unresponsive, we can still read it from other servers. Even though both are good for us, there are a few tradeoffs. One of the most critical tradeoffs in almost all distributed (and redundant) databases is data synchronization across all the redundant servers. So, in this chapter, we will see how distributed locking helps DynamoDB to manage data synchronization and redundancy...