On the basis of acceptability,
money has been classified into legal tender and
optional money. Legal tender money is enforced
by law. Optional money is that money which
may or may not be accepted as a means of
payment; it has no legal sanction. Different
credit instruments, like, cheques, bank drafts,
etc., are the examples of optional money.
ভাষা ও ভাষার উৎপত্তি
Plasma Physics (প্লাজমা পদার্থবিদ্যা)
Laser (লেজার)
Quantum materials (কোয়ান্টাম উপকরণ)
Particle physics (কণা পদার্থবিজ্ঞান)
Optics (অপটিক্স এবং ফোটোনিক্স)