Believe it or not, they do not all mean the same thing. Degree Conferral refers to the official date on which the University will post your degree to your transcript. The degree conferral date also indicates an approximate time for when students can expect to receive their diplomas. Graduation typically refers to the time when students complete their degrees. Some people also use this term to refer to the ceremony which takes place in June.
Commencement refers to the actual graduation ceremony.
There is only one commencement ceremony which usually takes place on the second Saturday in June. All students are welcome to participate in the commencement ceremony. Students may attend the commencement ceremony which occurs in the same calendar year as their official conferral date. Guest tickets are not required. Graduates must bring their reader's card to the ceremony.