и vs. а, saying "and". Help with that, please?

I've seen people use both "а" and "и" to say "and." Is this because of a change in topic, or is it OK to use it anytime?

There's a difference between "и" and "a". "И" is mostly used in simple recitation of objects or actions. "A" can be roughly replaced with words "but", "while", etc., and often there's some kind of contrasting statement.
For example:
Я люблю фрукты и овощи = I like fruits and vegetables - you can't use "a" here, it's always "и".
Я люблю фрукты, а мой брат - овощи = I like fruits, and (=while) my brother likes vegetables.

This is one of the most common problems of English speakers with Russian. Conjunction "а" sometimes is translated to English as "and", sometimes as "but". Though in Russian in most cases it is not interchangeable with "и" nor with "но". Very roughly: "а" is used to introduce a new or different meanings, "и" is used for the enumeration of the similar objects, "но" is used to describe limitations. Mostly.

Very roughly: "а" is used to introduce a new or different meanings, "и" is used for the enumeration of the similar objects, "но" is used to describe limitations. Mostly.[/QUOTE]

After reading through this forum I came across this topic. Could you give me a few sentences with "а", "и" and "но" + some explanations? Actually I don't know what you mean by nor "limitations" nor "new or different meanings".

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