POC means point of control. In a volume profile it is usually the price with the most traded volume; in a TPO profile it is the price with the most time-based prints.
The POC is a center-of-activity reference, not automatically support or resistance. A session can accept prices around it, migrate away from it, or pass through it without meaningful reaction.
When a briefing mentions a POC, preserve the profile and time window behind it. A prior RTH POC and an overnight POC describe different auctions.