Is there a big difference between asp.net and asp.net core?

Question

ASP.NET

Hello community! Tell me, please, is there a fundamental difference between asp.net and asp.net core?
I've been working on asp.net (.net 4.6.1) for half a year now and I'm looking for a new job on the sly. There are a number of interesting vacancies (projects) in which they write on asp.net core. I deliberately do not respond to such vacancies, because I have already jumped a lot on technologies (1c and Unity behind my back) and I want to finally concentrate on one thing.
I noticed that some vacancies require asp.net/asp.net core experience through a slash, as if these are interchangeable things and the employer does not see a fundamental difference between them.
Maybe I'm in vain sharing technologies and ignoring projects on Asp.Net Core? Is there a big difference between technologies?

Answer 1

There is no fundamental difference - if you are well versed in ASP NET, then you can easily switch to ASP NET Core.

Maybe I'm in vain sharing technologies and ignoring projects on Asp.Net Core?

In vain. Core is faster and has more features. The Framework is not relevant now and everyone is leaving it en masse. (Partly due to the fact that even MS transferred it only to security updates, that is, there will no longer be any new features)
At least all the projects on the Framework where I was either already in a state of transition, or had a transition to plans.
UPD: In .net 6, a new API for describing endpoints has also appeared:
(here is literally the whole hello world with it)

using Microsoft.AspNetCore.Builder;

var builder = WebApplication.CreateBuilder(args);
var app = builder.Build();

app.MapGet("/hello", () => "Hello, World!");

app.Run();

Answer 2

There is a difference.
For example, let's take the task of getting the user's IP address (Don't swear for creativity, I'm doing just such a task).
There are two options for choosing:
1 - Through Dns
2 - Through HttpContext
The difference is that when using Dns.GetHostEntry(Dns.GetHostName()) you can get a certain list of IP addresses and there seems to be no problems with this. But they are not there until the time when you work on Windows. This way of obtaining an IP WILL NOT work on other systems (Linux/Mac) and you will have trouble deploying to those systems.
Why?
Dns is a class that is included in the .Net Framework library, namely System.Net, at the same time HttpContext(HttpContextAccessor) is included in the Microsoft.AspNetCore.Http library, respectively, you will not have problems with deploying to other systems. We come
to that conclusion ( I think almost everyone who worked on a .Net Core system knows this) that the .Net Framework system is roughly tied to the Windows OS, and .Net Core is a multi-platform development platform