join() method in Python is used to combine elements of an iterable into a single string. It places the specified separator between each element. It is commonly used with lists and tuples, but it can work with any iterable whose elements are strings.

Example: Here the elements of a list are joined using a space as the separator.

words = ["Python", "is", "easy"]

result = " ".join(words)

print(result)

Python is easy

Explanation:

• List contains three string elements.
• " ".join(words) places a space between each element.
• Resulting string is stored in result and printed.

Syntax

separator.join ( iterable )

Parameters:

• separator: Its the string placed between the elements.
• iterable: Contains the string needed to be joined.

Joining List

List of string can be joined using any required separator.

languages = ["Python", "Java", "C++"]

result = ", ".join(languages)

print(result)

Python, Java, C++

Joining Tuple

join() also works with tuples containing strings.

items = ("Learn", "Python", "Fast")

result = " ".join(items)

print(result)

Learn Python Fast

Joining Sets

They can also be passed to join(). However, sets are unordered, so the order of elements in the resulting string is not guaranteed.

items = {"Python", "Java", "C++"}

result = ", ".join(items)

print(result)

C++, Java, Python

Joining Dictionary Keys

When a dictionary is passed directly to join(), Python iterates over its keys.

data = {
    "Name": 1,
    "Age": 2,
    "City": 3
}

result = "-".join(data)

print(result)

Name-Age-City

Joining a Generator

It can work with generators because generators are iterables.

words = (word for word in ["Python", "is", "fun"])

result = " ".join(words)

print(result)

Python is fun

Using Empty Separator

An empty string can be used as the separator when no character should appear between elements.

words = ["Py", "thon"]

result = "".join(words)

print(result)