Stock price when the opinion was issued
Basically the NASDAQ 100. Acts as a benchmark for a lot of people like himself. Extremely liquid. Trade, rather than invest. Top was around $550, and he thinks it will probably take out those highs before the end of the year.
Based on the look of the chart, he'd write calls against it with a strike of around $530-540. This way, you collect some premiums. If you don't want to get taken out, just keep rolling the strike price up.
The NASDAQ has been on fire and this represents that as a proxy. It is back to recent highs, so he would wait for a break to new highs, wait two days and then buy if it holds strength. He would not buy until the new highs have been made.