Hmmmm that is a wallie of a answer abd i know i will miss something. so gen has triggers which activate genjutsu, also you can find ways of breakng out of the gen by determining things about the gen which may be false. You can also have someone force foreign chakra into you disturbing the flow, also naruto tried showing the other way of spiking your chakra. Types of gen i would be guessing on this part but i imagine that those are eye technique,sound gen's and or smell which all are easy to tell the difference from.
Byakugan can see chakra when it is in a gen or disturbed as can sharingan and more likely rin. as for advantages it helps to delay an enemy or trap them leaving them wide open for a following attack.
disadvantages well itachi showed it best when he used ms it takes a serious toll on the user. and low level gen is easier to break out of.
Genjutsu are techniques used to trap the enemy in illusions. They can be cast in many number of ways, from using sound, to merely looking into the eyes of the user to fall under it. Aside of making illusions, Genjusu can be used to manipulate others. Advantages of genjutsu are that after the opponent has fallen for it, they are open for pretty much most attacks. Another advantage is that one of the only ways to snap out of high level genjutsu is by causing enough pain to once self that may leave them unable to fight. Disadvantages can be , that like Roju already stated, some of them have a great toll on the user, tiring them out. Low level Genjutsu can be easily snapped out of by causing a small amount of pain.
Before we get into actually talking about genjutsu and it's uses, we need to expand upon your knowledge in other places. Genjutsu works by altering your reality through the use of illusions and chakra but before you can learn about altering reality, you first have to understand your reality and surroundings first. Genjutsu manipulates one or more of your five senses and you need to have a strong sense of understanding of reality and your surroundings in order to know something is up and not right.
When you are placed inside a genjutsu, you must discover how it is just that, a genjutsu. People sometimes go into these long winded and pointless discussions on how they realize it's an illusion when you can notice small, simple things that can alarm you. Things that seem to happen suddenly and are unrealistic to the situation and scenario should be an alarming factor. Things like a Hozuki bio causing trees around to change should tip you off as well.
Recognizing is only half the battle, you must be able to counter it as well. Wasting time on long speeches on how you figure out may cost you the fight. In most cases, once you're placed under a genjutsu, you only have a few moments before another attack is sent your way. That means you have to reason very quickly and counter/defend against the genjutsu and then whatever jutsu may or may not be hurling towards you.
That being said, what all ways do you know of that can release one from a genjutsu? ^_^
-Pain ie stab yourself bite your tongue off stuff like that.
-Chakra disruption ie someone running their chakra into your body disturbing the flow.
-spiking your chakra like what naruto was taught by jiraiya.
- certain techniques will also work ie nagashi and I wanna say having byakugan and or sharingan.
- does not work on shadow clones from what has been shown in the anime.
There's probly way more but that's my knowledge so far and I don't look for answers I write what I know.
There are quite a few ways for someone to snap out of a genjutsu technique. One can simply cause pain to oneself, which would disrupt the genjutsu, however, the damage has to be greater the stronger the genjutsu used is. When fighting with a partner, if he is able to snap out of the genjutsu first or not trapped in it, he is able to use his own chakra to disrupt your flow of chakra, snapping out of the genjutsu. I think I have read of being able to use Chidori Nagashi to snap out of B rank or below genjutsu and I think there is a genjutsu called Kai to snap oneself out of a genjutsu by disrupting their own chakra flow.
Good overview, but let's go more into detail. Pain does indeed release you from Genjutsu. Tell me all about it, how it works, what it does, advantages, disadvantages, how you think it works, etc. There are no right or wrong answers.
From what think, by receiving pain, it causes a spike in your chakra, causing it to dispel the genjutsu. An advantage is that it is a pretty easy way to rid yourself of the illusions. A disadvantage is the fact that it only works for low level genjutsu as higher ones need more pain, which would be worse for the person causing him/her self pain as it would leave them unable to fight :3
Imo pain disrupts your sense of touch or feel so that being said pain works off the sense's and is one of the easier ways of freeing oneself from a genjutsu.
To go more into detail one can cause pain in amyway to there body as long as it is sufficient pain it wil work.
I also wanna think that the sense's are the main cause of gen so breaking it by using pain maoes sense as smell is hard to decipher while in gen and your eyes are obviously decieving you. hearing ie sound is also a main cause but i have yet to hear of sounds beimg able to free you.
Oh advantage is that you'll escape genjutsu using pain but disadvantage is that you will be wounded from whatever you try.