PS C:\PS> Get-Alias -name ls

CommandType   Name                        Definition
-----------   ----                        ----------
Alias      ls                         Get-ChildItem

PS C:\PS> Get-Alias -name dir

CommandType   Name                        Definition
-----------   ----                        ----------
Alias      dir                         Get-ChildItem

PS C:\PS> Get-Alias -name fl

CommandType   Name                        Definition
-----------   ----                        ----------
Alias      fl                         Format-List

PS C:\PS> Get-Alias -name ft

CommandType   Name                        Definition
-----------   ----                        ----------
Alias      ft                         Format-Table

PS C:\PS> dir alias: | where {$_.Definition.Startswith("Remove")}

CommandType   Name                        Definition
-----------   ----                        ----------
Alias      del                         Remove-Item
Alias      erase                        Remove-Item
Alias      rbp                         Remove-PSBreakpoint
Alias      rd                         Remove-Item
Alias      rdr                         Remove-PSDrive
Alias      ri                         Remove-Item
Alias      rjb                         Remove-Job
Alias      rm                         Remove-Item
Alias      rmdir                        Remove-Item
Alias      rmo                         Remove-Module
Alias      rp                         Remove-ItemProperty
Alias      rsn                         Remove-PSSession
Alias      rsnp                        Remove-PSSnapin
Alias      rv                         Remove-Variable
Alias      rwmi                        Remove-WMIObject

PS C:\PS> ls alias: | Group-Object definition | sort -Descending Count

Count Name           Group
----- ----           -----
  6 Remove-Item        {del, erase, rd, ri...}
  3 Set-Location       {cd, chdir, sl}
  3 Get-History        {ghy, h, history}
  3 Get-ChildItem       {dir, gci, ls}
  3 Get-Content        {cat, gc, type}
  3 Move-Item         {mi, move, mv}
  3 Copy-Item         {copy, cp, cpi}
  2 Start-Process       {saps, start}
  2 Set-Variable       {set, sv}
  2 Write-Output       {echo, write}
  2 Get-Process        {gps, ps}
  2 Invoke-History      {ihy, r}
  2 New-PSDrive        {mount, ndr}
  2 Stop-Process       {kill, spps}
  2 Rename-Item        {ren, rni}
  2 Get-Location       {gl, pwd}
  2 Compare-Object      {compare, diff}
  2 Where-Object       {?, where}
  2 ForEach-Object      {%, foreach}
  2 Clear-Host        {clear, cls}
  1 Out-Host         {oh}
  1 New-PSSession       {nsn}
  1 New-Variable       {nv}
  1 Out-GridView       {ogv}
  1 Pop-Location       {popd}
  1 Tee-Object        {tee}
  1 Remove-PSBreakpoint    {rbp}
  1 Receive-Job        {rcjb}
  1 Push-Location       {pushd}
  1 mkdir           {md}
  1 Measure-Object      {measure}
  1 help           {man}
  1 Remove-PSSnapin      {rsnp}
  1 Out-Printer        {lp}
  1 New-Item         {ni}
  1 New-Module        {nmo}
  1 New-Alias         {nal}
  1 Move-ItemProperty     {mp}
  1 Wait-Job         {wjb}
  1 Remove-PSDrive      {rdr}
  1 Start-Service       {sasv}
  1 Set-PSBreakpoint     {sbp}
  1 Set-ItemProperty     {sp}
  1 Start-Job         {sajb}
  1 Set-Alias         {sal}
  1 Start-Sleep        {sleep}
  1 Set-Item         {si}
  1 Select-Object       {select}
  1 Set-Content        {sc}
  1 Sort-Object        {sort}
  1 Remove-WMIObject     {rwmi}
  1 Remove-Module       {rmo}
  1 Rename-ItemProperty    {rnp}
  1 Stop-Service       {spsv}
  1 Set-WMIInstance      {swmi}
  1 Remove-Job        {rjb}
  1 Remove-Variable      {rv}
  1 Resolve-Path       {rvpa}
  1 Stop-Job         {spjb}
  1 Remove-ItemProperty    {rp}
  1 Remove-PSSession     {rsn}
  1 Exit-PSSession      {exsn}
  1 Format-Custom       {fc}
  1 Enter-PSSession      {etsn}
  1 Export-Csv        {epcsv}
  1 Export-PSSession     {epsn}
  1 Format-List        {fl}
  1 Get-PSBreakpoint     {gbp}
  1 Get-Command        {gcm}
  1 Get-Alias         {gal}
  1 Format-Table       {ft}
  1 Format-Wide        {fw}
  1 Export-Alias       {epal}
  1 Clear-History       {clhy}
  1 Clear-Item        {cli}
  1 Clear-Content       {clc}
  1 Add-Content        {ac}
  1 Add-PSSnapIn       {asnp}
  1 Clear-ItemProperty    {clp}
  1 Disable-PSBreakpoint   {dbp}
  1 Enable-PSBreakpoint    {ebp}
  1 Convert-Path       {cvpa}
  1 Clear-Variable      {clv}
  1 Copy-ItemProperty     {cpp}
  1 Invoke-Expression     {iex}
  1 Invoke-Item        {ii}
  1 Invoke-Command      {icm}
  1 Get-Variable       {gv}
  1 Get-WmiObject       {gwmi}
  1 Import-Alias       {ipal}
  1 powershell_ise.exe    {ise}
  1 Invoke-WMIMethod     {iwmi}
  1 Import-PSSession     {ipsn}
  1 Import-Csv        {ipcsv}
  1 Import-Module       {ipmo}
  1 Get-Unique        {gu}
  1 Get-Job          {gjb}
  1 Get-Member        {gm}
  1 Get-Item         {gi}
  1 Get-PSCallStack      {gcs}
  1 Get-PSDrive        {gdr}
  1 Get-Module        {gmo}
  1 Get-PSSnapIn       {gsnp}
  1 Get-Service        {gsv}
  1 Get-PSSession       {gsn}
  1 Get-ItemProperty     {gp}
  1 Group-Object       {group}

PS C:\PS> Set-Alias -Name Edit -Value notepad
PS C:\PS> Edit
PS C:\PS> $alias:Edit
notepad

PS C:\PS> Import-Alias alias.ps1
Import-Alias : Alias not allowed because an alias with the name 'ac' already exists.
At line:1 char:13
+ Import-Alias <<<< alias.ps1
  + CategoryInfo     : ResourceExists: (ac:String) [Import-Alias], SessionStateException
  + FullyQualifiedErrorId : AliasAlreadyExists,Microsoft.PowerShell.Commands.ImportAliasCommand

PS C:\PS> Export-Alias alias.ps1
PS C:\PS> Import-Alias -Force alias.ps1

gas c:\scripts\sqlscript.ps1

get-authenticodesignature c:\scripts\sqlscript.ps1