Two column layout in rmarkdown

2column_html_format.Rmd

---
title: "test"
output:
  html_document
---

```{r setup, include=FALSE}
knitr::opts_chunk$set(echo = FALSE)
```

## Two columns layout

by default, Rmarkdwon uses boostrap. Refer to
https://www.w3schools.com/bootstrap/bootstrap_grid_system.asp

:::: row
::: col-md-6
```{r cars}
plot(pressure, main = paste("Lorem Ipsum ",
                        "Ipsum lorem ipsum. ",
                        "\nLorem ipsum", sep=""))
```
:::

::: col-md-6
```{r pressure}
plot(pressure, main = paste("Lorem Ipsum ",
                        "Ipsum lorem ipsum. ",
                        "\nLorem ipsum", sep=""))
```
:::
::::