I am a beginner in cake decorating. Can someone please explain to me what "Tube 5" is? I want to make the Big Bird face cake and the recipe calls for using Tube 5 to decorate with. I don't know what this is. Is it like a decorating tip? Are tips and tubes synonymous?

Wilton use to refer to tips as tubes way back when. Somewhere along the way they started calling them tips. The numbers of 'tubes' and 'tips' should be the same, as long as we are talking about Wilton tips.

Here's a guide:

http://www.cakecentral.com/article42-Decorating-Tip-Numbers.html