What it means
The Meta Pixel, Google tag, TikTok Pixel and similar fire when someone views a page, adds to cart, or buys, reporting it back to the platform. That data powers conversion reporting, retargeting audiences, and bidding optimisation.
Why it matters
The pixel is still necessary but no longer sufficient. Privacy controls and ad-blockers eat into browser-side firing, which is why pixels are now paired with server-side tracking and the Conversions API to keep the signal whole.