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In this section of the course,

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we'll learn about the various types of smart pointers in c++ and how to use them.

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First, we'll understand why we need smart pointers at all.

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After all, there must be an issue with the way that raw pointers work

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that motivated the need for smart pointers.

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So we'll review some of the problems associated with raw pointers.

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Then we'll see what smart pointers are and understand how the address the issues with raw pointers.

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One of the most important concepts to understand in this section

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is that of ownership and RAII or resource acquisition is initialization.

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I'll go over this idiom since it's central to understanding not only smart pointers

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but resource management in general.

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Then we'll look at each type of c++ smart pointer and see how they work and how to use them.

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Ultimately, we want to write code that has no news and no deletes.

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So all the memory management is handled by c++.

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If c++ can automatically clean up the heat whenever a pointer is no longer needed,

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then we'll never leak memory, and we don't have to worry about needing to know when a pointer is no longer needed.

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That's the idea anyway. Smart pointers aren't perfect,

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but they can certainly make our code better in most cases.

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First, we'll learn about the unique pointer, which is exactly what it sounds like.

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A unique pointer to keep storage that is not shared and the ownership is clear.

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When you know who owns the pointer, then you know who needs to delete the pointer

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or at least c++ does.

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Then we'll learn about shared pointers. Shared pointers are pointers that share common heap

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storage and can be very useful.

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Then we'll learn about weak pointers, and how they can help us avoid a problem

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associated with shared pointers.

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Finally, we'll see how we can use custom deleters

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so that c++ can call a specific version of delete

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that does exactly what we want.

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Smart pointers are very important part of modern c++,

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and we want to use them whenever we can to help us manage memory.