What is the difference between ConfigureServices and Configure methods?

• ConfigureServices() and Configure() methods are used to register services and configure components within the request pipeline respectively.
• ConfigureServices() takes a parameter of type IServiceCollection.
• Configure() takes a parameter of type IApplicationBuilder with possible parameters of any Service which is registered in the ConfigureServices() method.
• an application should contain an ConfigureServices() method with an optional Configure() method.

public class Startup
{
    public void ConfigureServices(IServiceCollection services) 
    {
    }
    public void Configure(IApplicationBuilder app)
    {
    }
}