Focus Order
What Is Focus Order?
Focus order is the path the keyboard takes through a page. Press Tab and focus moves from one control to the next; focus order is what decides which control is next. When it works, the order matches what you see: the email field, then the password field, then Sign In. When it does not, pressing Tab from the email field can jump to the footer, then back to the middle of the form.
Why the Order Goes Wrong
Almost always because visual position and code position have drifted apart. A two-column layout is built as one column in the markup and then repositioned with CSS, so the eye reads left to right while the keyboard reads top to bottom of the source. Modal dialogs are a second common cause: the dialog appears on top, but focus is still moving through the page behind it.
Focus Order and Focus Visibility Are Different Problems
Focus order is where focus goes. Focus visibility is whether you can see where it landed. A page can have a perfectly logical order and no visible indicator, leaving the visitor pressing Tab blindly, or a bright visible indicator moving in an order that makes no sense. Both are needed, and an audit reports them separately.
How It Affects Real Users
Someone who cannot use a mouse, because of a motor impairment or because they are working from a screen reader, navigates entirely this way. Picture a checkout where Tab moves from the card number to the newsletter checkbox to the site footer and only then to the expiry date. The purchase is still technically possible. In practice most people abandon it, because they cannot tell whether they missed a required field.
Where Focus Order Shows Up in an Accessibility Review
Reviewers tab through the page from the top and compare what receives focus against what they see. Multi-column forms, custom dropdowns, modals, off-canvas menus and anything reordered with CSS attract the most findings. This is not something a scanner can settle, because the tool can read the sequence but cannot judge whether it makes sense to a person.