Spark is a platform for cluster computing. Spark lets you spread data and computations over clusters with multiple nodes (think of each node as a separate computer). Splitting up your data makes it easier to work with very large datasets because each node only works with a small amount of data.
As each node works on its own subset of the total data, it also carries out a part of the total calculations required, so that both data processing and computation are performed in parallel over the nodes in the cluster. It is a fact that parallel computation can make certain types of programming tasks much faster.
However, with greater computing power comes greater complexity.
Deciding whether or not Spark is the best solution for your problem takes some experience, but you can consider questions like:
Are you excited to learn more about Spark?