# Loop Functions

## Loop Functions in R

Loop functions are some of the most powerful functions in R. They are very easy to use, especially in an interactive setting, and make it possible do to a lot of work while writing less code. 

To start learning about loop functions, watch the following videos from Coursera, and return here afterward:

1. [Loop functions - lapply](https://www.coursera.org/learn/r-programming/lecture/t5iuo/loop-functions-lapply)
2. [Loop functions - apply](https://www.coursera.org/learn/r-programming/lecture/IUUhK/loop-functions-apply)
3. [Loop functions - mapply](https://www.coursera.org/learn/r-programming/lecture/EBnAr/loop-functions-mapply)
4. [Loop functions - tapply](https://www.coursera.org/learn/r-programming/lecture/w98BR/loop-functions-tapply)

These are the last videos from Coursera in this guide. However, you are encouraged to continue the course and finish it if you so choose.

## swirl Exercises

To practice everything you just learned about loop functions, complete the following swirl lessons:

1. swirl Lesson 10: lapply and sapply
2. swirl Lesson 11: vapply and tapply

## Congratulations!

If you made it here, then congratulations! You have successfully completed this section. Move to the next portion of the guide with the arrow buttons below.


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