An algorithm in the computer science world is a set of instructions that takes finite space and time to execute. It starts at an initial state of the application and then performs a set of instructions step by step to achieve the end result. 

Algorithms come in all shape and sizes, and all of them will fit the bill when you compare it with the overly generic definition of what an algorithm is. The big question is to decide which algorithm to use in which case and to make modifications to enhance its functionality based on the application's needs.

As I have shown in the use cases in previous chapters, most of the times, the algorithms that exist out there do not directly apply to the problems at hand. This is when a thorough understanding of the algorithm comes in handy. That is exactly what we will be doing in this chapter; we will take a look at a series of algorithms and then try to understand them better with the help of some examples.

In this chapter, we will discuss the following algorithms with some examples:

• Recursion
• Dijkstra
• Breadth First Search (BFS)
• Dynamic Programming
• Greedy Algorithm
• Branch And Bound

Let's set up a bare-bones Node.js project before we start looking at the use cases.