Hi I am new here, I absolutely love astrology and found this site and it's awesome and I have decided to join :) . I have been reading around and during topics people will say things like:
"It may be because my sun is opposite Uranus"

I understand about most things, like the sun sign and moon sign and ascendant, but I am finding it hard to understand what exactly trines and oppositions and squars and semisextiles exactly means.

if someone doesnt mind to take the time could you explain please? For example, my moon is trine with my Mercury... so does that mean I can easily epress myself in emotions (since my moon is pisces)...?

I am just a tid tad bit confused... lol. And sad to say I have googled it a thousand times and still dont seem to understand. It would be nice to get real  help haha !!! thanks :)

Conjunctions are two planets that work hand-in-hand; they're married.  Sometimes a good thing, sometimes not.  (That's why it's a "hard" aspect.)

Sextiles are planets that work together easily, but not quite as well as a trine.  Both aspects have a natural "flow" together and it's easy for the planets to get along -- sometimes too easy!

Squares and oppositions are two planets that butt heads.  They're after the same thing, but have different ways of getting it and it creates friction.  The opposition is a bit more harsh because the two planets have extremely different viewpoints that don't work together very well (or at all).

And, of course, the planets in the different aspects can alter the meaning.  If two planets get each other naturally, then a square or opposition isn't going to be as difficult to work with as it would with two planets that naturally disagree.  (Just like if your friend does something to irk you, it's easier to forgive than if your worst enemy did the same thing.)

It helps me when I think about it in terms of signs.  Discarding all the other variables, a Cancer will grok another Cancer completely (conjunct), can empathize with Pisces or Scorpio very well (trine), understands Taurus and Virgo even if they disagree (sextile), but has problems with Aries and Libra (square) because too often Cancer can't understand them, and Capricorn (opposed) will completely rub Cancer the wrong way because their worldview is skewed in Cancer's eyes.

I still don't understand the "minor" aspects like semisquares, quintiles, etc.  Sorry!  Hope this helps!  If not, I'm sure someone (everyone) here has a different explanation. 

Ohhh thank you thank you so much!!!! That helps lots :]