Howdy, new member. I'm relatively new myself.
To answer your question, I would say with definite uncertainty that what you have is a Yucca. We see a fair number of them here in Texas. I don't know which yucca it is, but I bet if you do a search in the Plants Database for Yucca, there will be a number of pictures that you can compare yours to.
I should also point out that there are many people here that might be more specific than I was.
Welcome and good luck!
