R programming predict interval difference between prediction and confidence

Question

I'm executing a regression model and I used the predict() function that R provides, What is the difference between this:

predict(data1.lm, interval="prediction")

and this:

predict(data1.lm, interval="confidence")

Answer 1

The intervals can include the uncertainty on the 

• estimated coefficients which is the confidence, 
• the variance  which is the noise in the observations, or 
• both which is the prediction.