What does CRISIL , ICRA and CARE ratings mean for bonds and treasury ?

Corporate fixed deposits and bonds are mandatorily required to get rated by a credit rating agency before going for a public issue. Credit rating signifies how risky or safe it is for you to invest in that financial instrument. CRISIL, CARE and ICRA are examples of some well known credit rating agencies. Following are some symbols that CRISIL gives to corporate bonds:-