Runspace

A runspace is a fundamental concept in PowerShell, representing an isolated environment where PowerShell commands are executed. Think of it as a sandbox or a session for running PowerShell code. Each runspace has its own state, including the current directory, loaded modules, variables, and scripts. This isolation is crucial for managing and executing scripts reliably, especially in scenarios where multiple scripts might be running concurrently or in complex applications.

When you open a PowerShell console, you are interacting with a default runspace. Programmatically, you can create and manage multiple runspaces within a single application. This allows for parallel execution of tasks. For instance, a script could launch several background jobs, each running in its own dedicated runspace, significantly speeding up operations that can be divided into independent parts.

The runspace manages the execution pipeline, handles script parsing, and tracks the state of the PowerShell session. When a command or script is invoked, it's executed within the context of a specific runspace. This object-oriented approach makes PowerShell highly extensible and allows developers to embed and control PowerShell functionality within their own applications. Understanding runspaces is key to advanced PowerShell scripting and development, enabling efficient resource management and parallel processing.