powershells get-help system is wonderful (not quite sure about the new update-help).
Here are some useful get-help topics:
about_Aliases HelpFile Describes how to use alternate names for cmdlets and commands in Windows
about_Arithmetic_Operators HelpFile Describes the operators that perform arithmetic in Windows PowerShell.
about_Arrays HelpFile SHORT DESCRIPTION
about_Assignment_Operators HelpFile Describes how to use operators to assign values to variables.
about_Automatic_Variables HelpFile Describes variables that store state information for Windows PowerShell.
about_Break HelpFile Describes a statement you can use to immediately exit Foreach, For, While,
about_Command_Precedence HelpFile Describes how Windows PowerShell determines which command to run.
about_Command_Syntax HelpFile Describes the syntax diagrams that are used in Windows PowerShell.
about_Comment_Based_Help HelpFile SHORT DESCRIPTION
about_CommonParameters HelpFile SHORT DESCRIPTION
about_Comparison_Operators HelpFile SHORT DESCRIPTION
about_Continue HelpFile Describes how the Continue statement immediately returns the program flow
about_Core_Commands HelpFile Lists the cmdlets that are designed for use with Windows PowerShell
about_Data_Sections HelpFile Explains Data sections, which isolate text strings and other read-only
about_Debuggers HelpFile Describes the Windows PowerShell debugger.
about_Do HelpFile Runs a statement list one or more times, subject to a While or Until
about_Environment_Variables HelpFile Describes how to access Windows environment variables in Windows
about_Escape_Characters HelpFile Introduces the escape character in Windows PowerShell and explains
about_Eventlogs HelpFile Windows PowerShell creates a Windows event log that is
about_Execution_Policies HelpFile Describes the Windows PowerShell execution policies and explains
about_For HelpFile SHORT DESCRIPTION
about_Foreach HelpFile Describes a language command you can use to traverse all the items in a
about_Format.ps1xml HelpFile The Format.ps1xml files in Windows PowerShell define the default display
about_Functions HelpFile Describes how to create and use functions in Windows PowerShell.
about_Functions_Advanced HelpFile Introduces advanced functions that act similar to cmdlets.
about_Functions_Advanced_Methods HelpFile Describes how functions that specify the CmdletBinding attribute can use
about_Functions_Advanced_Param… HelpFile Explains how to add parameters to advanced functions.
about_Functions_CmdletBindingA… HelpFile Describes the attribute that makes a function work like a
about_Functions_OutputTypeAttr… HelpFile SHORT DESCRIPTION
about_Group_Policy_Settings HelpFile Describes the Group Policy settings for Windows PowerShell
about_Hash_Tables HelpFile SHORT DESCRIPTION
about_History HelpFile Describes how to get and run commands in the command history.
about_If HelpFile Describes a language command you can use to run statement lists based
about_Jobs HelpFile Provides information about how Windows PowerShell background jobs run a
about_Job_Details HelpFile SHORT DESCRIPTION
about_Join HelpFile SHORT DESCRIPTION
about_Language_Keywords HelpFile SHORT DESCRIPTION
about_Line_Editing HelpFile Describes how to edit commands at the Windows PowerShell command prompt.
about_Locations HelpFile Describes how to access items from the working location in Windows
about_Logical_Operators HelpFile Describes the operators that connect statements in Windows PowerShell.
about_Methods HelpFile Describes how to use methods to perform actions on objects in Windows
about_Modules HelpFile Explains how to install, import, and use Windows PowerShell modules.
about_Objects HelpFile SHORT DESCRIPTION
about_Object_Creation HelpFile SHORT DESCRIPTION
about_Operators HelpFile Describes the operators that are supported by Windows PowerShell.
about_Operator_Precedence HelpFile Lists the Windows PowerShell operators in precedence order.
about_Parameters HelpFile SHORT DESCRIPTION
about_Parameters_Default_Values HelpFile SHORT DESCRIPTION
about_Parsing HelpFile Describes how Windows PowerShell parses commands.
about_Path_Syntax HelpFile Describes the full and relative path name formats in Windows PowerShell.
about_Pipelines HelpFile Combining commands into pipelines in the Windows PowerShell
about_PowerShell.exe HelpFile Explains how to use the PowerShell.exe command-line tool. Displays
about_PowerShell_Ise.exe HelpFile Explains how to use the PowerShell_Ise.exe command-line tool.
about_Preference_Variables HelpFile Variables that customize the behavior of Windows PowerShell
about_Profiles HelpFile Describes how to create and use a Windows PowerShell profile.
about_Prompts HelpFile SHORT DESCRIPTION
about_Properties HelpFile Describes how to use object properties in Windows PowerShell.
about_Providers HelpFile Describes how Windows PowerShell providers provide access to data and
about_PSSessions HelpFile Describes Windows PowerShell sessions (PSSessions) and explains how to
about_PSSession_Details HelpFile Provides detailed information about Windows PowerShell sessions and the
about_PSSnapins HelpFile Describes Windows PowerShell snap-ins and shows how to use and manage them.
about_Quoting_Rules HelpFile SHORT DESCRIPTION
about_Redirection HelpFile Explains how to redirect output from Windows PowerShell to text files.
about_Ref HelpFile Describes how to create and use a reference variable type.
about_Regular_Expressions HelpFile Describes regular expressions in Windows PowerShell.
about_Remote HelpFile Describes how to run remote commands in Windows PowerShell.
about_Remote_Disconnected_Sess… HelpFile Explains how to disconnect from and reconnect to a PSSession
about_Remote_FAQ HelpFile Contains questions and answers about running remote commands
about_Remote_Jobs HelpFile Describes how to run background jobs on remote computers.
about_Remote_Output HelpFile Describes how to interpret and format the output of remote commands.
about_Remote_Requirements HelpFile Describes the system requirements and configuration requirements for
about_Remote_Troubleshooting HelpFile Describes how to troubleshoot remote operations in Windows PowerShell.
about_Remote_Variables HelpFile Explains how to use local and remote variables in remote
about_Requires HelpFile Prevents a script from running without the required elements.
about_Reserved_Words HelpFile Lists the reserved words that cannot be used as identifiers because they
about_Return HelpFile Exits the current scope, which can be a function, script, or script block.
about_Run_With_PowerShell HelpFile Explains how to use the “Run with PowerShell” feature to run
about_Scopes HelpFile Explains the concept of scope in Windows PowerShell and shows how to set
about_Scripts HelpFile Describes how to run and write scripts in Windows PowerShell.
about_Script_Blocks HelpFile Defines what a script block is and explains how to use script blocks in
about_Script_Internationalization HelpFile Describes the script internationalization features of Windows PowerShell 2.0
about_Session_Configurations HelpFile Describes session configurations, which determine the users who can
about_Session_Configuration_Files HelpFile Describes session configuration files, which can be used in a
about_Signing HelpFile SHORT DESCRIPTION
about_Special_Characters HelpFile Describes the special characters that you can use to control how
about_Splatting HelpFile SHORT DESCRIPTION
about_Split HelpFile Explains how to use the Split operator to split one or more strings into
about_Switch HelpFile SHORT DESCRIPTION
about_Throw HelpFile Describes the Throw keyword, which generates a terminating error.
about_Transactions HelpFile Describes how to manage transacted operations in Windows PowerShell.
about_Trap HelpFile Describes a keyword that handles a terminating error.
about_Try_Catch_Finally HelpFile Describes how to use the Try, Catch, and Finally blocks to handle
about_Types.ps1xml HelpFile Explains how to use Types.ps1xml files to extend the types of objects
about_Type_Operators HelpFile Describes the operators that work with Microsoft .NET Framework types.
about_Updatable_Help HelpFile SHORT DESCRIPTION
about_Variables HelpFile Describes how variables store values that can be used in Windows
about_While HelpFile Describes a language statement that you can use to run a command block
about_Wildcards HelpFile Describes how to use wildcard characters in Windows PowerShell.
about_Windows_PowerShell_3.0 HelpFile Describes some of the new features that are included in
about_Windows_PowerShell_ISE HelpFile SHORT DESCRIPTION
about_WMI HelpFile SHORT DESCRIPTION
about_Wmi_Cmdlets HelpFile Provides background information about Windows Management Instrumentation
about_WQL HelpFile SHORT DESCRIPTION
about_WS-Management_Cmdlets HelpFile Provides an overview of Web Services for Management (WS-Management) as
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