Create a SharePoint Group using PowerShell

Requirement: Create new SharePoint Group using PowerShell
SharePoint groups to simplifies permission management by assigning a set of users to a group and assigning permission level to them through the group. There are default groups gets created based on the site template you choose while creating site collections, Such as Owners, Members and Visitors.

PowerShell to Create SharePoint Security Group
Here is my script to create new SharePoint group using PowerShell:

Add-PSSnapin Microsoft.SharePoint.PowerShell –ErrorAction SilentlyContinue

#Custom Function to Create new SharePoint Group
function Create-SPGroup
{  
    param ($SiteURL, $GroupName, $PermissionLevel, $GroupDescription)  

    try
    {
        #Get the Web
        $web = Get-SPWeb -Identity $SiteURL
        
        if($web -ne $null)
        {
            #Check if Group Exists already
            if ($web.SiteGroups[$GroupName] -ne $null)  
            {  
                write-Host "Group $GroupName exists Already!" -ForegroundColor Red 
            }  
            else  
            {  
                #Create SharePoint Group
                $Web.SiteGroups.Add($GroupName, $web.Site.Owner, $web.Site.Owner, $GroupDescription)  
                #Get the newly created group and assign permission to it
                $Group = $web.SiteGroups[$groupName]  
                $roleAssignment = new-object Microsoft.SharePoint.SPRoleAssignment($group)  
                $roleDefinition = $web.Site.RootWeb.RoleDefinitions[$permissionLevel]  
                $roleAssignment.RoleDefinitionBindings.Add($roleDefinition)  
                $web.RoleAssignments.Add($roleAssignment)  
                $web.Update()  

                write-Host "Group: $GroupName created successfully!" -ForegroundColor Green
            }  
 
            $web.Dispose() 
        }
    }
    catch [System.Exception]
    {
        write-host $_.Exception.ToString() -ForegroundColor Red 
    }
}

#Call the function to create Sharepoint group
Create-SPGroup "http://sales.crescent.com" "Sales Managers" "Edit" "Group for Sales Managers" 

This script creates SharePoint user group using PowerShell. You can also create SharePoint user groups from web UI How to Add a New User Group in SharePoint?