Space vs Tab Space - (NSData *)returnSomething { // uses 4 spaces for indentation return data; } Tabs - (NSData *)returnSomething { // uses 1 tab for indentation return data; } Line Length over 80 characters Line length is within 80 characters. /* width is within 80 characters */ Line length is within 100 characters. /* width is within 100 characters */ Line length is within 120 characters. /* width is within 120 characters */ Line length is within 150 characters. /* width is within 150 characters */ Brace Placement (Control Structure) Curlybrace with one space if (someInstance != nil) { //do stuff } Curlybrace with new line if (someInstance != nil) { //do stuff } Curlybrace with no space if (someInstance != nil){ //do stuff } Brace Placement (Methods) Curlybrace from new line - (void)clearAllDataWithCompletionBlock:(void (^)(NSString *))block { //do stuff } Curlybrace on same line - (void)clearAllDataWithCompletionBlock:(void (^)(NSString *))block { //do stuff }