PPM - Defining an Alias - Why is this needed? Can we skip this?

Hello All,

I have started configuring PPM 6.1 demo system.

I came across the following in the Config guide (SAP Portfolio and Project Management 6.1 SP01)

Defining an Alias --

By defining an alias in the HTTP service tree (transaction SICF), you can call the application

using a shorter, mnemonic URL

My default PPM URL is http://sapdemo3.local.com:8000/sap/bc/nwbc/

My questions

1. Do we define alias just for a shorter (user-friendly) URL?

2. Can we skip defining an alias?

3. Can some provide me an example of what alias you are using with reference to URL I have given above ?