The difference between geom_density(ggplot2) and density(base)

The difference between geom_density(ggplot2) and density(base)

I have a data in R like the following:
bag_id location_type event_ts
2 155 sorter 2012-01-02 17:06:05
3 305 arrival 2012-01-01 07:20:16
1 155 transfer 2012-01-02 15:57:54
4 692 arrival 2012-03-29 09:47:52
10 748 transfer 2012-01-08 17:26:02
11 748 sorter 2012-01-08 17:30:02
12 993 arrival 2012-01-23 08:58:54
13 1019 arrival 2012-01-09 07:17:02
14 1019 sorter 2012-01-09 07:33:15
15 1154 transfer 2012-01-12 21:07:50
where class(event_ts) is "POSIXct".
I wanted to find the density of bags at each location in different times.
I used the command *geom_density(ggplot2)* and I could plot it very nice.
I wonder if there is any difference between density(base) and this
command. I mean any difference about the methods that they are using or
the default bandwith that they are using and the like.
I need to add the densities to my data frame. If I had used the function
density(base), I knew how I can use the function approxfun to add these
values to my data frame. but I wonder if it is the same when I use
*geom_density(ggplot2)* .