Lies-Deception-Omission

Is there a difference in lies, deception or omission? Hmm? I was talking to somebody recently & this topic came up & when I was asked about which action was worse, it gave me chance to ponder the question & when I thought about it I realized that they probably are all the same if used in a deceitful context or manner but when used to protect, they probably are ok.
Example: When you know of an infraction or wrong doing of somebody & it has nothing to do with you or those you care about. If you don't say anything & the action wasn't life threatening, you probably are smart if you don't tell somebody (omission).
Example: If you are asked what your opinion is when somebody really likes what they have done but you don't like it at all. You can be honest & hurt this persons feelings or you can skirt around the issue by saying something like, "it wouldn't be my first choice but if you like it then that is all that is important" (deception).
Example: If somebody wants you to go to a party or social function & you don't care for the attitude or lifestyle of those in attendance & you tell the host that you can't come because you are busy. You avoid the problem & you don't offend the host. (lies)

You have to choose your own path through life but as you travel the complicated maze of life, remember that if you hurt people on the way, you are probably doing something wrong but if you are supporting people or making people happy then you are probably doing something right.
I don't approve of telling lies to people for the benefit of gain or recognition & an example would be, if you see somebody & they look nice, tell the truth & say so but if they don't look nice, don't lie. Dont say I sound good when I sing unless I do, don't say I smell good, look good or did something good, unless you really mean it. That also is a lie but for a completely different outcome.
The key to life in my opinion is to be honest, communicate well & to help others & treat them the way you want to be treated. Honest!