The following R code creates a scatterplot using ggplot2. Points on this plot are represented by identification numbers. The jitter option removes overlap between these plotted values.

#### Attach R libraries
library("ggplot2")


#### Generate random data set 
theData <- data.frame(id=1:20, xVar=sample(1:4, 20, replace=TRUE), yVar=sample(1:4, 20, replace=TRUE))


#### Plot scatterplot
set.seed(seed=658672)
p <- ggplot(theData)
p + theme_bw() + geom_text(aes(x=xVar,y=yVar,label=id),size=3,position=position_jitter(w=.2, h=.2))