SAP: What do you need to start learning SAPUI5?

[Sirion]

Hi, Emanuele! Welcome to Habr. Glad to see you here.

Frankly, I don't know much about SAP. So I want to ask:

1. Is OpenUI5 a general purpose UI framework, or it's designed to work with SAP ecosystem?
2. Could I see some kind of comparison between OpenUI5 and mainstream frameworks?

[StErMi]

Hi Sirion, happy to be here ;)
SAP has many many faces that touch a lot of different technologies. If you want to keep a look at all the services available on SCP (SAP Cloud Platform) you can take a look at the Capabilities page. It has evolved a lot since '80s ;)

To answer to your questions:

1. OpenUI5 is the open source version of SAPUI5 (the latter has priority support and a couple of pre-made controls not yet in the open source version). UI5 is a general purpose framework similar to Vue/ReactJS/Angular. SAPUI5 is the perfect choice if you're working on SAP envoirnment for two main reason: SAP use a lot of OData to talk between backend-to-backend and frontend-to-backend and it's natively supported by UI5. The second reason is that UI5 offers a lot of pre-made UI controls that speed up your app-building and allows you to easily extend them or create new one from scatch. Using that framework allows you to easily comply to the SAP Fiori Design Pattern.
2. Compared to other frameworks is still a little bit behind (in term of performance) but it's improving a lot and they're (core team) investing really a huge amount of resources. It's still a must if you need to develop in a SAP ecosystem for the reasons above