Krav Maga vs Aikido: Which is better and what's the difference, you ask? In a nutshell, the difference is that one is an Asian martial art designed to promote peace, and the other is a street fighting style hybrid of various martial art disciplines. As for which is better, it depends on your goals.
Aikido was developed by a Russo-Japanese War veteran named Morihei Ueshiba. Ueshiba studied Jujitsu and other disciplines before the war and continued to study martial arts afterward. In his 40's, Ueshiba realized that the true purpose of martial arts is to cultivate and tap into the supreme love that animates all beings. This is apparent in the word "Aikido", which means "The Way of Harmony."
The purpose of Aikido is to harmonize with conflict. It is a whole system of handling conflict with the highest wisdom, ideally without anyone getting hurt. The spiritual principles of Aikido are outlined in Ueshiba's book, "The Art of Peace."
The self defense aspects of Aikido involve using the attacker's force against him until the attack stops. Some Aikido training uses swords and others are bare handed. There are no Aikido tournaments because the philosophy states that Aikido should not be used for selfish purposes. That includes win-lose styles of sparring. Aikido is designed so that everyone wins because we are all one in spirit.
Krav Maga is a fusion of a variety of martial arts and hand to hand combat techniques. It was developed in Israel during their war of independence, and it continues to be the official self defense system of the Israeli military. The words "Krav Maga" literally mean "contact combat" in the Hebrew language. The purpose of Krav Maga is to whoop ass in the case of an attack. It is not considered a sport because there are no rules, so there are no Krav Maga tournaments.
Krav Maga training teaches you to how to defend yourself in gun and knife attacks as well as multiple attacker gang style scenarios. With practice, you will learn how to be keenly aware of your environment so that attacks become less likely. You will also learn how to use objects within your environment as self defense weapons and how to get out of choke holds, headlocks and other holds. Unlike some martial arts, the Krav Maga practitioner's motion is continuous. Action is decisive and possibly deadly if necessary.
What is the difference between Krav Maga and Aikido? It is now clear that the motives and goals of each are like night and day even though both are used as methods of self defense.
Which is better? That is up to you to decide. Do you want to take down an attacker by any means necessary and learn hand to hand military combat techniques? Do you want to simply prevent injury while cultivating the wisdom of your mind, body and spirit? Define martial arts training goals and see if they match up with the values of either Krav Maga or Aikido.