A trip is shorter. A trip could be a weekend break away with your wife or it could be a business trip. (You leave on Friday your hometown on Friday and return home Sunday). When you go on a trip, you usually only visit one town or city. When someone goes travelling they visit a number of different cities towns etc. Travelling is always longer than a trip. You could go travelling for a week,month,year.

a trip is usually short, and you always come back from a trip. You can go for a trip from your town to a nearby lake - in the morning, and come back in the evening. If you are travelling, you usually go from one place, to another, to another, to another... returning home is not important. Travelling is usually longer. You can take a gap year and travel around Europe. I hope this is helpful. :)