Displaying date in SAS
Try the following:

data sample; 
Input ID name $ Dob;
informat DOB date9. ; 
format DOB mmddyy10. ; 
datalines;
1 abc 22jan1996
2 xyz 25aug1996
;
run;
Proc print data = sample;
run; 


I have added the informat line. The problem with the original code is that you have not told SAS what is the format that DOB will come in. In this case: 22jan1996 is of date9. format, so I added the informat telling SAS that the data will come in this way.

The format DOB line tells SAS to display the data as mmddyy10. which makes 22jan1996 look like 01/22/1996.

Lastly, the . before the ; in the format/informat lines specifies that it is a format type. There are character formats: $8. or numeric formats Best12. etc...