Please see the attached link.
To clear things up, the bill wasn't printed in Philadelphia. That's the Federal Reserve District that distributed the bill, but it was printed in Washington. Please see the question "What is the value of a 1950 US 100 dollar bill?" for more information.
The green seal indicates that your bill is a Federal Reserve Note. Please see the question "What is the value of a 1950 C US 10 dollar federal reserve note?" for more information.
There are no 1950 $1 bills. The nearest dates are 1935 and 1957. Please look again and post a new question.
There were many different denominations of bills with that date and series letter. Please post a new, separate question with the bill's denomination.
If there is no letter or an A, B, C, or D next to the date it's worth $100 in worn condition, up to $140 if almost like new. If there's an E next to the date, $140.-$210. The serial number doesn't usually identify a bill or affect its value. The series letter next to the date and the bill's seal color are more important.
Despite their age, $20 bills from the 1950 series rarely sell for more than a dollar or two above face value.
Please check your bill again. There are 1950 A and 1950 C $10 bills but they're different. The series letter is next to the date; any other letter isn't a series letter. Neither one is rare, though. As of 03/2012 they would retail for $12 to $15 in averaged condition.
Please check your bill again, including the banner across the top. A blue seal would indicate that it's a silver certificate, but no $10 silver certificates were dated 1950.
There was no C series 1966 $100 US Notes, only plain and A. Please see the Related Questions for more information.
C = 100
100
That's not an error. The phrase "In God We Trust" wasn't added to U.S. currency (paper money) until 1957.