What is a stack good for?

A stack is a specialized list data structure that enforces LIFO (last in, first out) ordering of data. Thinking of a stack as a physical stack of plates (and data items as the plates), you can only take the last plate that you added to the stack.

The stack data structure is among the most useful structures in Computer Science. Stack usage appears at all levels of programming, from operating system kernels to high level languages like those in the .NET framework. Saying that a stack is useful is easy to say, but let's look at some tasks that a stack can be used for:

Stack Usage Examples

• Expression evaluation (i.e. postfix evaluation)
• Expression parsing (i.e. convert infix to postfix notation)
• Balanced brace checking
• Solving search problems (i.e. crossword puzzle solver, chess playing algorithms)

In a future posting a detailed example that uses a stack will be provided.

Additional Resources
System.Collections.Stack Class (Microsoft)
Stacks (Wikipedia)