#Images producted by plot(x) depend on the class of x:
methods(plot)

#Examples:
class(sin); plot(sin,xlim=c(-pi,pi),xlab="x",ylab="sin(x)")

x=rpois (1000 ,1); y=table(x);class(y);plot(y)

# save a numeric vector containing 72 monthly observations
myvector = .1*(1:72)+sin((1:72)*pi/12) + 
  rnorm(72,mean=0,sd=.3)

# from Jan 2009 to Dec 2014 as a time series object
myts = ts(myvector, start=c(2009, 1), end=c(2014, 12), 
          frequency=12)
class(myts); plot(myts,col="red")

r=rnorm(1E3,1); w=density(r); class(w)
plot(w)