What it measures
P/E ratio is share price divided by earnings per share. A P/E of 15 means investors are currently paying 15 times the company's per-share annual earnings for one share.
A high P/E isn't automatically expensive and a low one isn't automatically cheap, it depends heavily on what sector a company is in and how fast it's actually growing. A fast-growing technology company and a stable, mature bank can both be fairly priced at very different P/E levels for genuinely different reasons.
A worked example
A share trades at 91.40 and the company reported earnings of 6.10 per share over the last year. P/E: 91.40 / 6.10 ≈ 15.0.
How Kobo & Cents uses it
P/E sits in the valuation and growth category alongside free cash flow and revenue growth rate, and like every other metric here, it's read as a sector-relative percentile, never a fixed "above this number is expensive" rule that would mean something different for a bank than it does for a tech company.