Importance of Sessions in Web Applications
Sessions bridge this gap by providing a means to preserve user-specific data across multiple requests within a defined period.

• Maintain User Identity: Sessions are instrumental in user authentication and authorization processes. They allow web applications to identify and track users across various interactions, ensuring secure access to restricted resources.
• Customized User Experience: Sessions facilitate the personalization of user experiences by storing user preferences, settings, and browsing history. This enables applications to tailor content and functionality based on individual user profiles.
• Shopping Carts and E-commerce: In e-commerce applications, sessions are indispensable for managing shopping carts and order processing. By persisting cart contents and user selections across page transitions, sessions streamline the purchasing journey and enhance user convenience.
• Form Persistence: Sessions enable the retention of form data entered by users, safeguarding against data loss during navigation or submission errors. This ensures a seamless and uninterrupted form-filling experience.
• Tracking User Activity: Sessions empower web analytics and tracking mechanisms by storing user session data, such as page views, interactions, and session duration. This information aids in understanding user behavior and optimizing website performance.

Implement Session Management in ASP.NET Core MVC
Create a New ASP.NET Core MVC Project: Start by creating a new ASP.NET Core MVC project in Visual Studio or using the .NET CLI.

Install Required Packages
Install the required packages for session management using NuGet Package Manager or the .NET CLI. In this example, we'll need the Microsoft.AspNetCore.Session package.

Configure Services
In the ConfigureServices method of the Startup class, add the session services using services.AddSession().

Configure Middleware
In the Configure method of the Startup class, use the session middleware using the app.UseSession().

Create Controllers
Create controllers to handle your application's logic. For this example, we'll use HomeController and RecordsController.

Here I have created a home cotroller with an Index action method to set data into session.
public class HomeController : Controller
{
    private readonly ILogger<HomeController> _logger;

    public HomeController(ILogger<HomeController> logger)
    {
        _logger = logger;
    }

    public IActionResult Index()
    {
        // Add list of records to session
        var records = new List<Record>
        {
            new Record { Id = 1, Name = "Record 1" },
            new Record { Id = 2, Name = "Record 2" },
            // Add more records here as needed
        };

        var serializedRecords = JsonSerializer.Serialize(records);
        HttpContext.Session.SetString("Records", serializedRecords);
        return RedirectToAction("GetRecords", "Records");
    }
}

Store Data in Session
In one of your controller actions (for example, the Index action of HomeController), store the data you want to maintain in the session. Serialize complex types like lists into strings or byte arrays before storing them.

I have stored data using var serializedRecords = JsonSerializer.Serialize(records);

Retrieve Data from Session
In another controller action (for example, the GetRecords action of RecordsController), retrieve the data from the session. Deserialize the stored data back into its original type if necessary.

public class RecordsController : Controller
{
    public IActionResult GetRecords()
    {
        // Retrieve list of records from session
        var records = HttpContext.Session.Get<List<Record>>("Records");
        return View(records);
    }
}

Summary
Session management is a fundamental aspect of web development, enabling developers to create interactive, personalized, and secure web applications.