"Provides high-performance and low-allocating types that serialize objects to JavaScript Object Notation (JSON) text and deserialize JSON text to objects, with UTF-8 support built-in. Also provides types to read and write JSON text encoded as UTF-8, and to create an in-memory document object model (DOM), that is read-only, for random access of the JSON elements within a structured view of the data.Commonly Used Types:System.Text.Json.JsonSerializerSystem.Text.Json.JsonDocumentSystem.Text.Json.JsonElementSystem.Text.Json.Utf8JsonWriterSystem.Text.Json.Utf8JsonReader When using NuGet 3.x this package requires at least version 3.4."