The US and UK ratings.

The meaning of rating is an opinion of the ability and willingness of an issuer to make timely payments on a debt instrument, such as a bond, over the life of that instrument.
Ratings companies like Standard and Poor and Moody are the big names in the US.
Ratings are not recommendations to buy or sell, nor are they a guarantee that default will not occur.
Investors use ratings to help price the credit risk of fixed-income securities they may buy or sell. Many also use ratings as limits on their investment parameters and as means for expanding their investment horizons to markets or security types they do not cover by their own analysis. Because major investors globally rely on Moody’s ratings, the ratings help to provide issuers of debt with stable, flexible access to those sources of capital.
This is the description of Moody's ratings:-
Investment Grade:-
Aaa - “gilt edged”
Aa1, Aa2, Aa3 - high-grade
A1, A2, A3 - upper-medium grade
Baa1, Baa2, Baa3 - medium grade
Speculative Grade:-
Ba1, Ba2, Ba3 - speculative elements
B1, B2, B3 - lack characteristics of a desirable investment
Caa1, Caa2, Caa3 - bonds of poor standing
Ca - highly speculative
C - lowest rating, extremely poor prospects of attaining any real investment standing

The U.S. and the U.K. have moved “substantially” closer to losing their AAA credit ratings as the cost of servicing their debt rose, according to Moody’s Investors Service.
The U.S. government will spend about 7 percent of its revenue servicing debt in 2010 and almost 11 percent in 2013, according to the baseline scenario of moderate economic recovery, fiscal adjustments in line with government plans and a gradual increase in interest rates, Moody’s said.
The U.K. is likely to spend 7 percent of revenue servicing debt this year and 9 percent in 2013, rising to almost 12 percent under the adverse scenario, Moody’s said.
The Dow,Monday is 4 market days to index/options expiry.
Asian index/options expiry 31/03/10.

9:30am:--A flat mild opening gap down with a bearish morning star.

10:30am:--A bearish spin at session MAV.

11:30am:--Morning session low with bullish short-cover.

12:30noon:--Retrace to bear resistance.Inverted bull noticed.

1:30pm:--Usual consolidation time.Holding near the MAV resistance line with reluctance to pierce through,a shooting star.

2:30pm:--Pullback to bear pivot support,a dragonfly doji.

3:30pm:--MAV resistance line broken,heading for the high.

4:00pm:--A bullish fresh candlestick closing with no upper shadow.

Last Thursday's candlestick body has been covered for the second time leaving a long lower shadow and a new candlestick body spinning at its high.

A good result from The Empire Manufacturing Index and industrial production for February also aided the market move.

Concerns about an overheating economy in China have fed persistent concerns about tighter monetary policy which affected Asian trading today.