Also, for the record, Arduino is basically open source, on purpose, so there is Arduino branded HW but also third party equipment which is usually as good and less costly. All the SW and IDE is free from Arduino, their language is a superset of C++. Ironically, given my (surely correct) estimation about Arduino enthusiasts being mostly men and boys, due to inherent temperament and interests, one of the best third party vendors for Arduino HW is Adafruit Industries, headed by Limor Fried (a woman, MIT graduate). They make good stuff.