A website backup is a copy of the site's files and content, stored separately, that can restore the site if something goes badly wrong: a hosting failure, a hacked site, an accidental deletion, a bad update. Most business owners assume this is happening automatically. It's worth actually confirming rather than assuming.
Ask who is responsible for it
If a developer or agency built the site, ask directly whether backups are part of the arrangement, how often they run, and where they're stored. If the answer is vague, that's itself useful information.
Ask how far back backups go
A backup taken once, months ago, is far less useful than a recent one. Find out the actual retention: is it the last backup only, or several recent versions going back weeks?
Ask where backups are stored
A backup stored on the same server as the live site doesn't protect against a server-level failure or a full hosting account compromise. A meaningful backup lives somewhere separate: a different storage provider, a different account.
Ask whether a restore has ever actually been tested
A backup that's never been restored is an assumption, not a guarantee. Some backup systems quietly fail for months before anyone notices, because nobody checks until the day it's actually needed.
For a static site, the situation is simpler
A site built from source files (like this one) that live in a version-controlled project folder already has a form of backup built into the workflow itself: the ability to rebuild the entire site from source at any time. That's a meaningfully different risk profile than a site whose only copy lives inside a database on a single server.
Questions
How often should backups run?
For a site that changes often (frequent content updates, an e-commerce store), daily. For a mostly static site that changes rarely, weekly or after each significant update is usually sufficient.
What's the actual cost of not having a backup?
If something goes wrong with no backup, the realistic options are rebuilding from scratch or losing content permanently. For a business whose site represents real ongoing investment, that risk is disproportionate to the small effort backups take.
Does my hosting provider back things up automatically?
Some do, some don't, and the ones that do vary widely in retention and reliability. This is exactly the kind of assumption worth confirming directly rather than guessing.