the applications, systems, and architectures that deal with handling the data and logic fed to frontend.

server

a computer hardware/software dedicated to running your backends applications i.e servers, database systems etc

inhouse / on-premise

you own the computers and hardware and keep them with you physically

cloud

computers and hardware owned by someone else, and are present somewhere else in the world, accessible to you via the internet

serverless / edge

there’s no true thing as serverless. it’s just a marketing term.

https://www.youtube.com/watch?v=90pVRK49AQM

in modern cloud computing, instead of renting and managing dedicated servers, serverless is auto managed and the technicals are abstracted away from you. i.e underlying servers, scaling, load balancing, failures etc

one off functions

it can be reactive (database triggers), or restful (HTTP endpoints)

mini chunks of business logic hosted somewhere on the cloud, like single functions

ex - aws lambda, google cloud functions