In Indian Language Sanskrit – ‘Shstra’ is a field of science, study like,

  1. rasAyana-shAstra is (chemistry),
  2. khagol-Shastra is (astronomy),
  3. artha-shAstra is economics and politics,
  4. chhanda-shAstra is study of verses, meter, poetry,
  5. nATya-shAstra is dramatics, theater.

Some classics works are called xyz-sUtra. These are part of the shAstra, but composed in form of tight formulae, like kAma-sUtra, yoga-sUtra, chhanda-sUtra.The below shloka show importance and characteristics of Shastra is from opening chapter of Hitopadesha, the king who was on a morning stroll along the river, hears some students reciting their homework early in the morning. they recited two shloka-s, one of which is this, the second we will cover later.It shows the importance of shAstra, science, fields of study.

अनेकसंशयोच्छेदि, परोक्षार्थस्य दर्शकम् ।सर्वस्य लोचनं शास्त्रं, यस्य नास्त्यन्ध एव सः ॥

हितोपदेश-सुभाषित-श्लोकाः – 0.10 written by Sri Narayan Pandit in 11th Century

MEANING :

अनेक संशयों को दूर करनेवाला, परोक्ष वस्तु को दिखानेवाला, और सबका नेत्ररुप शास्त्र जिस ने पढा नहि, वह इन्सान (आँख होने के बावजुद) अंधा है ।Shastra or Science , which clears many doubts, which shows the meaning which is hidden (non-direct), is like an eye for everyone. One who does not possess it, is indeed blind.Einstein has high regards and respect for Indian Ancient Knowledge and Experience on Scient and Technology.