WooCommerce is a WordPress plugin that turns your site into a shop: product catalogue, cart, payments, shipping, discounts. It’s popular, has many extensions and themes, and you manage both content and shop in one WordPress dashboard.
It works well for small and medium catalogues and when you want simplicity and low hosting cost. For very large product ranges, complex pricing or advanced integrations, a dedicated platform (e.g. PrestaShop) may be better.
Pros: one base (site + shop), large community, many ready-made solutions. Cons: with a big shop it can be slower and needs good hosting and regular updates.