Nice pics of what, where?
Once again, it sounds like pedantry, but what I'm trying to say is that if you start to think about precisely what you want to achieve, then the question will come. You might even work out the answer yourself.
There's threads on here about 'wedding photography' and technique, but at a wedding the pro will shoot:
Macro
Candid portraits
Posed portraits of: single people, couples and groups.
Still life
Contre jour
High key
Low key
Natural light
On camera flash (as fill)
On and off camera flash as the main light
A bit of landscape
Night photography
Action
And typically use 3 zooms and a macro lens along with some fast primes.
Now you're obviously not thinking of all of that, just stick on a standard zoom and flashgun and use your imagination. One of the most interesting techniques is dancefloor shots mixing the DJ lights for movement with your flash for freezing the action. Take the prime lens to hang about round the bar, blend in to the environment and shoot some low light candids (takes patience and keeps you away from drinking though).
As a guest I'd only take a DSLR to a wedding if I was on a diet or a course of antibiotics

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