PowerShell is an object-oriented automation and configuration management framework from Microsoft. Unlike traditional command-line interfaces that work with text, PowerShell works with .NET objects, making it more powerful for system administration tasks.

Key differences:

• Object-based: Commands return .NET objects instead of text
• Cmdlet structure: Uses verb-noun syntax (Get-Process, Set-Location)
• Pipeline: Objects flow through the pipeline, not just text
• Integrated scripting: Built-in scripting language with full .NET access
• Cross-platform: PowerShell Core runs on Windows, Linux, and macOS

PowerShell ISE (Integrated Scripting Environment): A graphical interface for writing, testing, and debugging PowerShell scripts. It's Windows-only and comes with Windows PowerShell.

PowerShell Core: The cross-platform version built on .NET Core, designed to run on Windows, Linux, and macOS.

Key differences:

• Platform support: ISE is Windows-only; Core is cross-platform
• Base framework: ISE uses .NET Framework; Core uses .NET Core
• Performance: Core is generally faster and more lightweight
• Module compatibility: Some Windows PowerShell modules aren't compatible with Core
• Development: Core is actively developed; ISE development has stopped

Execution policy is a security feature that controls which PowerShell scripts can run on a system. It helps prevent malicious scripts from executing accidentally.

Execution policy levels:

• Restricted: No scripts can run (default on client systems)
• RemoteSigned: Local scripts run freely; remote scripts must be signed
• AllSigned: All scripts must be digitally signed
• Unrestricted: All scripts run with warnings for remote scripts
• Bypass: Nothing is blocked; no warnings
• Undefined: No execution policy is set

PowerShell cmdlets follow a consistent verb-noun naming pattern that makes them intuitive and discoverable. The verb describes the action, and the noun describes what the action is performed on.

Common verbs:

• Get: Retrieves information
• Set: Changes or configures something
• New: Creates something new
• Remove: Deletes something
• Start/Stop: Controls services or processes
• Test: Validates or checks something

Examples: Get-Service, Set-Location, New-Item, Remove-File, Start-Process

PowerShell recognizes four types of commands in this order of precedence:

1. Aliases: Shortened names for cmdlets (ls for Get-ChildItem)
2. Functions: User-defined commands written in PowerShell
3. Cmdlets: Compiled .NET classes that follow verb-noun syntax
4. External executables: Traditional command-line programs

You can use Get-Command to identify command types and find available commands.

These are formatting cmdlets that control how output is displayed:

Format-Table: Displays output in tabular format with columns. Good for comparing multiple objects side by side.

Format-List: Displays output as a list with property names and values. Better for detailed view of single objects or when properties have long values.

Out-GridView: Opens output in a separate GUI window with sorting, filtering, and selection capabilities. Interactive and user-friendly for data exploration.