“instruction level parallelism” and “processor level parallelism”

What’s the difference between instruction level parallelism (ILP) and processor level parallelism? That’s a question asked by a user of this site. Parallelism is the execution of two or more operations at the same time by homogenous functional units. There’s a good explanation of the two types of parallelism in the presentation embedded below. See especially pages 2,3,4,9 and 12.