How exactly are microservices implemented?

Microservices should not split by logic_one/two/three. It's sud separate by the business domain which may work in independent, There's much logic in a domain of business.Back to e-commerce design. Assume that few kind of domain like (login/auth, user, order, shipping).So each domain may consider as 1 module/domain

• Login/auth => the service has a responsibility to manage login token, authorization
• User => the service manages all user profile
• Order => the service where user can create/execute/cancel... an order
• Shipping => the service where you can update/manage the status of shipping with 3rd party...

So, if you have only logic_1, logic_2,... It's 1 service/ 1 module. Above just an example, an actual microservice system is split quite small domain.

• a different in Microservice system is, the client(mobile/web...) only communitate with a service call API-GateWay instead of touch to core services (login/auth, user, order, shipping...) directly. It's like 1-stop service lol

Note: An application not using/apply Microservices pattern does not mean that that is not a good design.