GCC stands for GNU C Compiler, it's a solid compiler that works well on the *nix kernels, there's a port of it on cygwin which is arguably slower but still works. Whether it's the best or not depends on what platform you are working on and with what you're trying to make on it.
Standard Postcard-a standard postcard mails First Class at current rate of 35Â¢. The smallest maiLabel size for ANY postcard is 3Â½â³ x 5.â³. The largest postcard size for mailing at the 35Â¢ rate is 4Â¼â³ x 6.â³. The paper thickness must be at least 0.007 â³ and not more than 0.016 â³ in thickness.
Large postcards can measure up to 6 ââ high, 11 Â½â long and Â¼â thick, but they cost as much as a First-Class Letter ($0.47 and up) to send. To qualify for postcard pricing, your mailer must be at least 3 Â½â high, 5â long and 0.007â thick (approximately the thickness of an index card), but no more than 4 Â¼â high, 6â long, or 0.016â thick.