Fast data fetching and grouping information

In the eighth part we recapped the content from parts 1-7 and learned how to use hash maps. HashMap and ArrayList are some of the most used data structures in programming. The benefit of HashMaps is that looking up information by key is really fast — this efficiency is really important for good user experience.

Hash maps are widely used in different kind of programs. For example, phonebook programs that can be used to look up information by phone numbers use Hash maps or Hash map like data structures for storing data and for efficient fetching of the data. Similarly, searching for user's bank account information when using a credit card is based on a data structure that is similar to hash maps.

What is more, we also learned that HashMap enables us to group data — for example one phone number or bank account can have many owners.

The eighth part also started the second part of this course. If you just jumped in, welcome aboard! Finally, please take a moment to answer a self-reflective survey on the learning goals of the eighth part.

Remember to check your points from the ball on the bottom-right corner of the material!