What is The Islamic Ruling on Marriage?

According to many scholars, marriage could fall into any one of the 5 categories of Islamic jurisprudence, depending on the individual and the circumstance that is particular to him/her. It is important for every concerned Muslim to understand these rulings.
1. Wajib (Mandatory)
2. Mustahab (Recommended)
3. Mubah (Allowed/Permitted)
4. Makrooh (Disliked)
5. Muharram (Impermissible)