The p value is effectively the % chance something happened by coincidence, and not because of a real effect. Like flipping a coin and getting the same side several times in a row. P value is an assessment of that likelihood. Less than .05 means a less than 5% chance of that. I don’t know what the other bit is, except it was likely a method of statistical analysis.
It’s a way of saying that the results they found were very unlikely to be due to chance.