What exactly does Judaism think on cheating (all types)?

Shalom, Thank you for your question. The topic of cheating is a large one. Let's try to address some of the issues involved. Cheating can mean different things in English - 1. Cheating in an exam or schoolwork – this is where a person who has not prepared properly copies answers (or work) from someone else (or from other sources). According to Judaism a person doing so breaks many laws. Firstly, “genavat da'at” which is the forbidden act of presenting a false image of oneself in order to take advantage of others. A person presents themselves as knowing the material, when in fact they don't. Secondly, this can lead to a staeling of money – as a person may receive a job based (even in part) on their exam results, and get paid accordingly, when in fact they do not deserve such a payment. This is a form of theft. Thirdly, if they get caught (which is more likely to happen than people think – just look at the news and see how many stories come out years after an event about people's past wrong doing), then there could be an element of desecration of G-d's Name. This is especially so if the person is known to be a religious Jew, they make Judaism look bad. 2. Cheating in a game – apart from some of the issues listed above, we can add here the sin of causing other people pain and suffering (the other people playing). Imagine the pain of losing to someone, only to find out that they cheated. 3. Cheating on one's spouse – sometimes the term “cheating” is used to refer to extra material affairs. Here there are additional sins of adultery and other connected sins. 4. Cheating in business – this involves many other sins, such as theft. We can add to all the above that usually cheating involves the sin of telling lies. Sometimes it involves slander and gossip. In short – Judaism is certainly anti-cheating! Blessings.