====== Working Directory ======
Getting 
<code>> getwd()
[1] "/home/paul/research"
> setwd("Bayes")
> getwd()
[1] "/home/paul/research/Bayes"
</code>

<code>
setwd("c:/r_data")
getwd()
</code>
====== Saving Workspace ======
<code>> save.image()</code>

====== Command History ======
<code>> history()             # Default 25
> history(100)          # Show 100 most recent lines of history
> history(Inf)          # Show entire saved history
</code>
====== Saving the Result of the Previous Command ======
<code>> aVeryLongRunningFunction()     # Oops! Forgot to save the result!
[1] 147.6549
> x <- .Last.value               # Capture the result now
> x
[1] 147.6549
</code>
====== Displaying the Search Path ======
<code>> search()</code> Gives a list of attached packages (see library), and R objects, usually data.frames.

====== Load and attach packages ======
<code>library(packagename)</code>
library and require load and attach add-on packages.
NOTE: no quote on package name.
<code>detach(packagename)</code>

====== Built-in Datasets ======
Find out available data set.
<code>data()</code>
Choose a specific data set from a specific package name.
<code>> data(dsname, package="pkgname")</code>
<code>> require(graphics)
> plot(pressure, xlab = "Temperature (deg C)",
     ylab = "Pressure (mm of Hg)",
     main = "pressure data: Vapor Pressure of Mercury")
     </code>
<code>> plot(faithful, xlab = "eruptions",
     ylab = "waiting",
     main = "old faithful erruption and waiting ratio")
</code>
{{faithful_data_graphic.png}}

<code>> data(Cars93, package="MASS") </code>
<code>> data(package="pkgname") </code>

====== List of Installed Packages ======
library()

====== Installing Packages ======
<code>> install.packages("packagename")</code>

====== Running a Script ======
<code>> source("myScript.R")</code>