Examples of STLs

1. vector: a dynamic array that can grow or shrink in size
2. list: a doubly linked list that allows for efficient insertion and deletion of elements
3. map: a container that stores key-value pairs in a sorted order
4. set: a container that stores unique elements in a sorted order
5. stack: a container that follows the Last In First Out (LIFO) principle
6. queue: a container that follows the First In First Out (FIFO) principle
7. priority_queue: a container that allows for efficient retrieval of the highest priority element
8. deque: a double-ended queue that allows for efficient insertion and deletion at both ends
9. algorithm: a collection of functions for performing common operations on containers, such as sorting and searching.

STL (Standard Template Library) is a set of predefined data structures and algorithms that can be used within C++ programs. Here are some examples of STLs:

1. Containers:
- `vector`: Dynamic array that automatically resizes as elements are added or removed.
- `list`: Doubly linked list that allows for efficient insertion and deletion of elements.
- `map`: Key-value store that provides fast lookup and sorting capabilities.
- `set`: Collection of unique elements that are sorted automatically.

2. Iterators:
- `vector::iterator`: Iterator that points to individual elements within a vector.
- `list::iterator`: Iterator that points to elements within a linked list.

3. Algorithms:
- `sort`: Sorts a container in ascending order.
- `find`: Finds the first occurrence of an element in a container.
- `count`: Counts the number of occurrences of an element in a container.

4. Functors:
- `less`: Comparator function that returns true if the first argument is less than the second.

5. Utility Classes:
- `pair`: Class that represents a pair of elements.
- `tuple`: Class that represents a tuple of multiple elements.

Examples of Using STLs:

```cpp
// Create a vector of integers
vector v = {1, 2, 3, 4, 5};

// Iterate through the vector using an iterator
for (vector::iterator it = v.begin(); it != v.end(); ++it) {
cout << -it << " ";
}

// Sort the vector in ascending order
sort(v.begin(), v.end());

// Create a map of countries and their capitals
map capitals;
capitals["USA"] = "Washington D.C.";
capitals["France"] = "Paris";

// Find the capital of a country
string capital = capitals["France"];
```