RStudio & Running Code

RStudio is the standard workspace for R — a single window that combines a script editor, a live console, and panes for your variables, plots, and help, so you can write and run R comfortably.

Learn RStudio & Running Code in our free R course — a beginner-friendly interactive lesson with worked examples, a practice exercise and a quick reference.

Part of the free R course at LearnCodingFast — hands-on lessons with examples you run in your browser, plus practice exercises and a quick quiz.

By the end of this lesson you'll know how R and RStudio relate, the difference between the console and a script, how to run code line by line or all at once, and how the working directory affects file paths.

What You'll Learn in This Lesson

1️⃣ Scripts: Code You Keep

A script is a plain text file (ending in .R ) full of R commands. Unlike typing into the console, a script is a permanent record you can re-run, edit, and share. Inside RStudio you write in the top-left editor pane and send lines to the console to run them.

Notice cat() prints values without quotes and lets you mix text and numbers, while "\\n" adds a line break. message() is handy for status updates that aren't part of your results.

2️⃣ The Console: Instant Feedback

The console runs code the moment you press Enter — perfect for quick checks. Two functions are invaluable for exploring: ls() lists the objects you've created, and str() ("structure") shows the shape of any object at a glance.

str() told us we have a numeric vector of 3 values: num [1:3] 1 2 3 . You'll reach for str() constantly once you start loading real data.

3️⃣ The Working Directory

When you read or write files, R uses the working directory as its starting point. getwd() shows it; setwd("path") changes it. Getting this right prevents the most common beginner frustration: "R can't find my file."

Your turn. Fill in the # TODO blank and run it, comparing with the expected output.

Write this one from scratch using the outline, then run it and check it against the example output.

📋 Quick Reference — Running Code

Practice quiz

What is the relationship between R and RStudio?

  • RStudio is the language; R is the editor
  • R is the language/engine; RStudio is an IDE around it
  • They are the same program
  • R replaced RStudio

Answer: R is the language/engine; RStudio is an IDE around it. R is the language and engine; RStudio is an IDE that sits on top of it.

What file extension does an R script use?

  • .R
  • .py
  • .txt
  • .rmd

Answer: .R. R scripts are plain text files ending in .R.

Which function lists the objects you have created this session?

  • str()
  • getwd()
  • ls()
  • list()

Answer: ls(). ls() lists the names of objects in your environment.

What does getwd() return?

  • The R version
  • A list of files
  • Your variables
  • The current working directory path

Answer: The current working directory path. getwd() shows the folder R uses as its working directory.

Which function gives a compact summary of an object's structure?

  • str()
  • ls()
  • cat()
  • message()

Answer: str(). str() reports the structure and type of any object.

What does cat() do compared to printing?

  • Saves to a file
  • Prints values without quotes, mixing text and numbers
  • Only prints numbers
  • Returns a value silently

Answer: Prints values without quotes, mixing text and numbers. cat() concatenates and prints without quotation marks.

What does " " produce inside cat()?

  • A tab
  • A backslash
  • A newline (line break)
  • A space

Answer: A newline (line break). is the newline escape, so output starts on a new line.

How do you run an entire saved script from the console?

  • run("a.R")
  • import("a.R")
  • exec("a.R")
  • source("a.R")

Answer: source("a.R"). source("a.R") executes every line of the saved file in order.

What is the keyboard shortcut to run the current line in RStudio?

  • Ctrl/Cmd + Enter
  • Ctrl + S
  • Alt + R
  • Shift + Space

Answer: Ctrl/Cmd + Enter. Ctrl/Cmd + Enter sends the current line to the console and advances.

Why does an RStudio Project (.Rproj) help with file paths?

  • It compiles your code
  • It hides the console
  • It sets the working directory automatically
  • It installs packages

Answer: It sets the working directory automatically. A Project sets the working directory for you, avoiding path headaches.