I had been helping a student revise a personal statement for his college applications. He had made major changes, worked hard to perfect it, and finally left one afternoon satisfied. The next morning he came in, looking slightly concerned.
"I printed it on some paper my Dad had at home," he said. "But I think there's something wrong with it."
I took a lot at it. It was fine. The printing was nice and crisp. On quality paper.
"What's wrong with it?" I asked.
"I don't know what it is," he said, "but there's some kind of writing on the paper. You can see it if you hold it up to the light."
I held it up, and of course! "That's the watermark," I said. "It probably means that this is a high-quality paper."
"So, there's nothing wrong with it?"
"No," I said. "In fact, when you print out your resume, you want to put it on thick, nice paper like this, not on plain white paper."
"OK, but why do they put it there?"