Shopify lets businesses sell products online without building an entire commerce system themselves.
That sounds obvious until you think about everything behind a functioning store. Payments, inventory, checkout, orders, taxes, shipping, mobile performance, and integrations all have to work.
Shopify handles much of that foundation.
The ecosystem is one of its strengths, but it can also become a source of extra cost once a store starts adding applications and custom features.
For most businesses that simply want to sell products online reliably, however, Shopify belongs on the shortlist immediately.
Pros
Easy to launch. Strong checkout. Large ecosystem. Capable of supporting significant growth.
Cons
Extra applications and customization can increase cost and complexity.
My take
For most online sellers, Shopify is popular for a very practical reason.