What does LLP stand for? As in the example name "Flood Law Group, LLP".
It means Limited liability partnership.
Basically, limited liability, means that the liabilities of the company (the debts) can't be transferred to the partner that have limited liability of the company.
So, if the company can't repay it's debts, the partner with limited liability can inject capital in the company, but don't have any obligations to do so.
I guess that you can find more information on the Wikipedia article about that: http://en.wikipedia.org/wiki/Limited_liability_partnership