Good advice from Brett. Basal testing is going without your food and insulin at meal-times to see if your basal insulin (lantus) is set at the right dose, you only need to do it if you suspect that your basal is wrong when you see high or low bg readings between meals or through the night, if your bg control is fine then I wouldn't worry about it for now.
Try and purchase the book Think Like a Pancreas by Gary Scheiner as it covers jjust about everything you need to know about type 1 diabetes, it's cheap enough on Amazon and cost around £12.