Introduction to PowerShell

Overview

• PowerShell video series: From basics to mastery.
• Assumes prior knowledge of command lines (e.g., cd, ls).
• Built on .NET framework.

PowerShell Setup

• Windows comes with an older version (v5).
• Recommended to download the latest version from GitHub for various platforms.

PowerShell Basics

Objects vs Text

• Commands return objects instead of text.
• Objects contain properties (e.g., file name, path, extension).
• Powershell displays objects in a readable text format (table or list).

Object Manipulation

• Use pipes | to pass objects between commands.
• Format-List: Lists object properties.
• Format-Table: Displays objects in table view.

Key Commands

Get-Process

• Retrieves all running processes.
• Displays in table view by default.

Command Analysis

• Properties like Name, ID, etc., shown along top of tables.
• Use Format-List to view object properties in list format.

Measure

• Analyzes objects (e.g., counts them).
• Can calculate statistics like average, sum.

Advanced PowerShell Usage

Where

• Filters objects based on conditions.
• Syntax: Where {condition}.
• Conditions use $_.property -eq 'value'.

Sort

• Orders objects by specified properties.
• Syntax: Sort-Object {property}.

ForEach

• Executes actions for each object.
• Can filter down to specific properties.
• Syntax: ForEach-Object {action}.

Practical Example

• Get processes with ID > 4000, calculate average CPU time.
  1. Use Get-Process.
  2. Filter IDs using Where.
  3. Extract CPU property with ForEach.
  4. Calculate average with Measure.

Conclusion

• Covered objects, pipes, and key commands: Measure, Where, Sort, ForEach.
• Next video: Deep dive into command parameters, aliases, and discovery.