Business portfolio.
A business portfolio is the container that holds everything your business owns on Meta: ad accounts, Pages, Instagram accounts, datasets and the people who can use them. Meta's help pages now call it a business portfolio, and you may still hear people use the older name, Business Manager.
It matters because whoever owns the portfolio owns the assets inside it. If your ads were set up inside someone else's portfolio, such as a previous agency's, you may find you cannot see your own history or take it with you.
For example, a garden center has its Page and ad account inside its own business portfolio and gives us access as a partner. If the relationship ended, access would be removed and the center would keep everything. Had we set it up in our own portfolio, the center would lose its ad history the day we parted.
Ad account.
The ad account is where your campaigns live, where Meta records your spend and results, and where your payment method and currency are held. A business can have more than one.
Its currency and time zone are set when it is created, and changing either means opening a new ad account, so they affect how your figures line up with your own accounts.
For example, a guest house with an ad account set to a different currency from the one it banks in will see spend reported in the ad account's currency, and the monthly figure will differ from the amount on the card statement because of the exchange rate.
Facebook Page and Instagram account.
Your ads run in the name of your Facebook Page and, if you connect one, your Instagram account. Those are what people see as the advertiser, and they are also where comments and messages arrive.
A Page with an empty history or an unmonitored inbox makes ads less convincing. Somebody needs to answer the comments on your ads.
For example, if you are a physiotherapist and your ad runs under a Page with no recent posts and three unanswered questions in the comments, a would-be patient may well decide you have closed.
Meta Pixel.
The Meta Pixel is a small piece of code on your website that tells Meta when someone does something, such as viewing a product, starting a checkout or sending an inquiry form. It is what lets Meta count results that happen on your website.
It is now managed inside a dataset, but people still call the browser-based code the pixel. Used alone it can miss events, which is one reason it is paired with the Conversions API.
For example, if you are a florist with a pixel installed, every completed order on your website sends Meta a purchase event. If the checkout is rebuilt and the pixel is not put back on the new thank-you page, Meta sees no sales while your till keeps ringing.
See also ConversionsCookie consent
Dataset.
A dataset is the single place where Meta collects the events sent from your website, app, shop or customer records. The pixel and the Conversions API both feed into it, and it is where you check that events are arriving.
It matters because Meta can only learn from, and report on, what reaches the dataset. A dataset that is missing events or receiving duplicates makes every figure in your report less reliable.
For example, a dentist's dataset shows inquiry events arriving from the pixel every day but none from the server connection. That tells us half the tracking is not working, even though the ads are still running.