When should I use PowerShell.AddCommand() and when should I use PowerShell.AddScript()? [duplicate]

I'm using C# and PowerShell to automate git commands to sync a lot of repositories. I found two ways of executing powershell commands:

• PowerShell.AddScript();
• PowerShell.AddCommand();

However, the documentation is really sparse on exactly what the difference is between the two methods. I have created two examples below using each of the two methods:

Running PowerShell commands with AddScript():

using (PowerShell powershell = PowerShell.Create())
{
    powershell.AddScript(@"git pull");
    var result powershell.Invoke();
}

Running PowerShell commands with AddCommand():

using (PowerShell powershell = PowerShell.Create())
{
    var command = new PSCommand();
    command.AddStatement().AddCommand("git").AddArgument("pull");
    powershell.Commands = command;
    var result = powershell.Invoke();
}

Both of the examples work as expected, but I would like to know what the difference is between AddScript() and Addcommand(). When would I use one method over the other? Are there advantaged/disadvantages with using one over the other?