My question involves criminal law for the state of: Nebraska

I am trying to get a better understanding of this statue: - habitual criminal statute.

This is the first paragraph: "(1) Whoever has been twice convicted of a crime, sentenced, and committed to prison, in this or any other state or by the United States or once in this state and once at least in any other state or by the United States, for terms of not less than one year each shall, upon conviction of a felony committed in this state, be deemed to be a habitual criminal and shall be punished by imprisonment in a Department of Correctional Services adult correctional facility for a mandatory minimum term of ten years and a maximum term of not more than sixty years, except that:"

Does it have to be the same crime (burglary, assault, etc) or the same type of crime (felony, misdemeanor)? If someone is convicted twice of a felony, would the prosecution suggest this habitual criminal statute to the judge in sentencing?

Someone mentioned this to me when discussing my ex's legal troubles. He is on trial for a felony and already has felony burglary on his record, felony aggravated assault and I believe felony DUI because he has more than three. I think four? Right now his charges are class II felonies which is 1-50 years. He has not been convicted yet and could very well be found not guilty I realize. I just do not think he realizes what he faces if he is found guilty and heard about this and wondered about it. I have no concern if he goes to prison but I had not heard of this statute until someone mentioned it and it seemed a little confusing to me.