What It Is
A database table is one organized list inside a database. If the database is a filing cabinet, each table is a drawer holding one kind of thing. Each row is a single record, and each column is a detail about it. A customers table might have one row per customer and columns for name, email and phone. WordPress creates its own set of tables for posts, users, comments and settings.
Why It Matters for Your Business
This matters because plugins often add tables of their own and may leave them behind after you remove the plugin. Over years, a site can collect leftover tables and old data that slow things down. A shop that has tried three different booking plugins, for example, may still carry data from all three, making backups larger and the site a little slower.
Good to Know
Tip: before removing a plugin that stores important data, such as form entries or bookings, export that data first. Deleting a plugin can delete its tables too. If you want to clean out old tables, take a full backup beforehand and have a developer confirm which ones are safe to remove.