---
title: 'This is the Title of Your Report Generated from R Markdown'
author: 'Vinh "MBALearnsToCode" Luong'
output:
  pdf_document:
    fig_caption: yes
fontsize: 12
geometry: margin=1.0in
---
<!-- comment: the above block between the two sets of triple dashes specify the Title of the document and some common formatting settings --> 


# What is Markdown?

[**Markdown**](http://daringfireball.net/projects/markdown) is an easy text file format that allows you to write up a document and apply stylings to create highly presentable output that can be published in various ways, including as PDF and as HTML webpages.


# Common Markdown syntax

Refer to the PDF output (created by "**Knit PDF**" in this RStudio window) to see how the below inputs are rendered in the final PDF output:

# Make a 1st-Level Header by inserting 1 hash character in front

## Make a 2nd-Level Header by inserting 2 hash characters in front

### Make a 3rd-Level Header by inserting 3 hash characters in front

_make italic text by putting 1 underline character at each end_

**make bold text by putting 2 star characters at each end**

**_then, obviously, this is how to make bold italic text_**

Make an numbered (ordered) list by simply putting "1."", "2."", "3.", etc., like so:

1. First item
2. Second item
3. Third item

Make an unordered list by putting "-" and a space in front of each item, like so:

- Unordered item
- Unordered item
- Unordered item

Make [hyperlinked text, e.g. referring to Google.com](http://www.google.com) like this.

Images can be embedded easily, with a caption too, like Figure 1 below:

![Chicago Booth logo](http://pbs.twimg.com/profile_images/447102503071789057/J_XkI6lI.jpeg)


# Embedding R code in R Markdown

The real power of R Markdown is in allowing you to embed R code into your document, and get the code executed and its results presented nicely the output - so that you can tell a wholesome, coherent story of your analysis.

You can insert R code to be run between the triple back-ticks like so:

```{r}
library(ggplot2)   # comment: load GGPlot2 package 
summary(cars)   # summarize Cars data set
```

R code blocks run sequentially, so you can continue with your R analysis in a separate code block, e.g. to make a plot like so: (note the figure width and heigth (in inches) settings in the {})

```{r fig.height=3, fig.width=4}
qplot(speed, dist, data=cars) + geom_smooth()   # a quick plot
```

Note that in the above examples:

- Each code block is repeated (echoed),
- Each code block's results are displayed, and
- All messages / warnings from running the R code are displayed

in the output document. Sometimes we may want to alter these display behaviors for our needs.

You can set a code block to be **not** echoed by specifying ***echo=FALSE*** like the following code block, which silently sets a variable **RVar** to value 1.2:

```{r echo=FALSE}
RVar = 1.2
```

You can hide the outputs from a code block by specifying ***results='hide'*** like in the following code block, which will not display the variable *RVar*'s value:

```{r results='hide'}
print(RVar)
```

You can hide messages and/or warnings by specifying ***message=FALSE*** and/or ***warning=FALSE***:

```{r fig.height=3, fig.width=4, message=FALSE, warning=FALSE}
qplot(speed, dist, data=cars) + geom_smooth()   # a quick plot without messages / warnings
```

Lastly, you can run certain short R code "in-line" and display its value by putting the code between single back-ticks, e.g. like in referring to the value of the *RVar* variable: RVar's value is currently *`r RVar`*.

THE END.