Short term extremum
The indicator determines and marks the short-term lows and highs of the market on the chart according to Larry Williams` book “Long-term secrets to short-term trading”.
“Any time there is a daily low with higher lows on both sides of it, that low will be a short-term low. We know this because a study of market action will show that prices descended in the low day, then failed to make a new low, and thus turned up, marking that ultimate low as a short-term point. A short-term market high is just the opposite. Here we will see a high with lower highs on both sides of it. What this says is that prices rallied up to the zenith of that middle day, then began to move back down, and in the process formed a short-term high. For our purposes in identifying short-term swing points, we will simply ignore inside days and the possible short-term points they produce.”