السلام عليكم
كيف الحال ياحلم عمري
بعطيك البعض من الكلمات ممكن تستفيدي منها
from1840 was used telegraphy after that come first telephone was inventor samuel
in1886 hertz verified experimentally that electrical energy could be radiated and thos proved the existence of electromagnetic waves
in 1960 come digital telphone and communication satellites