Lecture
This lecture discusses the three primary usages of the 'static' keyword in C++. It begins with local static variables, explaining their limited scope and permanent lifetime, which allows them to retain their value between function calls. The instructor illustrates this with a function that counts the number of calls using a static variable. Next, the lecture covers global static variables, emphasizing their confidentiality within a module and their accessibility by all functions within that module. The instructor warns against exposing such variables in module interfaces. Finally, the lecture addresses static class attributes, which share a single value across all instances of a class, highlighting their limited scope to the class and permanent lifetime. The importance of proper initialization and encapsulation is stressed throughout, along with practical examples to clarify these concepts. The lecture concludes with a quiz to reinforce understanding of the material presented.