If You Could Read My Mind

While there are those who claim they can talk with the animals, most of us we need a few clues to understand what is going on in our cat little head.
In common with human behavior, body language is a very powerful means of communication for cats. If we can learn to interpret the various intricacies of our cat's posture then we can indeed begin to read their mind.
It must be accepted that this is not easy. As humans, we are used to displaying body language so we have a head start in reading it too. However, even if we had a tail and ear movement abilities, we'd probably use them in a different way to a cat.
All is not lost though. Some cat body language is very familiar to us and some is downright obvious: if kitty wandering around our feet and the cat food bowl in the morning doesn't say to us 'Feed Me' then we've got a lot of work to do. We can use common sense to translate other behavior too. A cat lying on its back, legs and feet splayed should tell us that our kitty is relaxed, and probably very content (would you expose all your vulnerable body areas if threatened?). Likewise a cat sitting or lying with outstretched front and back legs is feeling pretty at ease in its surroundings, it's not getting ready for fight or flight.
We are all familiar with a cat pressing the side of its head on our body and we probably know a little bit about scenting. A little bit more thought will help us understand that our cat is marking us and is therefore taking ownership (think wedding ring or band), so we can safely assume kitty loves us.
Dog owners know very well what a wagging tail means. But they may be getting the message a little confused if their cat sweeps its tail at half height. It means quite the opposite.
When a cat jumps on our lap at starts treading up and down or kneading us then we should again feel wanted. Some cats do this more than others and it has been interpreted as the cat attempting to stimulate us for milk. This is questionable though because it is not usually associated with other hunger behavior and is carried well into adulthood. It's more likely simply our cat making a bed in its favorite place.
What about the ears? Basically: up = good, down = bad, if they are flat against the back then beware.
Take time to learn the different movements your cat makes and you too can claim to talk with the animals.

Here's a useful ready-reckoner for quick reference