Python - String Concatenation

In Python, you can put two or more strings together to create a new string. This process is called string concatenation, and it's done using the "+" symbol. It lets you combine separate strings into a single one.

For example, suppose we have two strings, "Hello" and "World". We can use the "+" sign to join them together:

```

greeting = "Hello"

name = "World"

message = greeting + " " + name

print(message)

```

This will output the string "Hello World". Note that we have added a space between the two strings using a string literal " ".

We can also concatenate strings using the "join" method. This method takes an iterable of strings and concatenates them with a specified separator.

```

fruits = ["apple", "banana", "orange"]

separator = ", "

fruit_string = separator.join(fruits)

print(fruit_string)

```

This will output the string "apple, banana, orange". Note that we have specified the separator as ", ".

It is important to note that string concatenation can be a computationally expensive operation, especially when dealing with large strings or many concatenations. In such cases, it is better to use string formatting or other string manipulation techniques to achieve the desired result. 

In summary, String concatenation is the process of combining two or more strings into a single string. It is achieved using the "+" operator or the "join" method. It is important to use efficient string manipulation techniques when dealing with large strings or many concatenations.