data manipulation for plotting

Hi,

   i'd like to plot some data that I have with the value on the x axis and freq
   on the y axis.

   So, I need to calculate the freq a value is seen within my data vector

   for example, say i have a vector of data

   data=c(1,1,1,4,5,5,6)

   I want

   values<-c(1,4,5,6)

   freq<-c(3,1,2,1)

   in order to enable me to plot this. Sorry, i'm new to R. What is standard
   procedure here for plotting the data vector?

   cheers

   Rich