Your name needs to be as per your passport
Check your passport first (don’t be lazy, get off your arse and find it)! When I worked as a travel agent, you would be surprised how many people would tell me their name was Chuck Bass (for instance), but it was actually Charles Bartholomew Bass on their passport, or vice versa. I once had a William who swore his name was William but it was Will on his passport (weird). Or they would tell me their name was Reese Witherspoon, but it was really Laura Jeanne Reese Witherspoon and she used her middle name instead of her first name. Once your flight is booked and paid for there is sometimes no turning back. All of these mishaps result in you having to pay hefty change fees or booking brand new tickets as you MUST have your name as per your passport! The terms and conditions (you know that small stuff that no one ever reads, well sometimes it is important) will always state this.
Does my middle name need to be on my ticket? If your middle name is on your passport, but not on your ticket, in most cases this is not an issue (but does depend on the airline e.g. Vietnam Airlines require middle names on tickets). However, if your middle name is not on your passport, but is on your ticket, this is an issue. If you are unsure what to put, check with the airline (and always note the person’s name that you spoke to, what office they are in and what number you called them on for your records).
Have two or three middle names and they don’t fit on your ticket? Once again check with the airline to confirm what to do.
Why are names so important? Since 9/11, airline and border security have tightened and they want to make sure that the right people are getting on the plane. So, all in all, it’s for your safety.