Indo-Aryan or Indian languages comprise many different local dialects (desi-bhæsæ), but very close to one another. There are two main groups (or families) of Indian languages, namely, Sanskrit and Prakrit, which are very similar to each other.
(1) Sanskrit, used by the Brahmans of educated class, who could spend much time on education and earn their living or livelihood by education, contained the words constructed or formed strictly in accordance with the grammatical rules and so it did not undergo many changes throughout its long history.
(2) Prakrits, however, used by the common people who had to spend more time on their livelihood than on education, inevitably underwent many changes, generation by generation, according to the time (kala), locality (desa) and individual (puggala), and comprise many different dialects which are very similar to one another, such as "Pali, Magadhi, Addha-Magadhi, Soraseni, Maha-ratthi, Pesaci, Apabhramsa (early Prakrit), and Hindi, Bengæli etc. (later Prakrit).
The Buddha or Omniscient one, skillful in all the Indian languages of his time, went on religious tour for 45 years, in many different parts of Central India (Majjhima-desa) in order to teach and propagate His Dhamma (Teaching of Truth) to the people for liberating them from worldly sufferings and leading them to Nibbana, eternal bliss. As a result, numerous people from different parts of India came to the Buddha and entered the Buddhist Order (Samgha). And consequently their own dialects, slightly variant from, but very close to Pali, intruded upon the Pali literature.
Moreover, after the passing away (Parinibbana) of the Buddha, His numerous missionary disciples, generation by generation, worked hard to teach and propagate the Buddha's Dhamma or Buddhism, not only in different parts of India, but also in neighbouring countries, such as Ceylon (¢rø-la³kæ), Nepal, Tibet, Pakistan, Afghanistan, Bengal, China and South-east Asian countries. When Buddhism declined in India, due to the Hindus and Muslims, Ceylon (and South India) came to the front in place of India and became the centre of Buddhism, by widely learning the Buddhist scriptures and writing numerous commentaries, sub commentaries and many other books (ganthantara) on various topics, such as the traditional Pali grammars and Pali dictionaries etc. mainly based on the traditional Sanskrit words. For the above-said reasons, Sanskrit and Prakrit languages exercised a great influence on the later Pali words.
European(or Euro-Aryan)languages and Indian(or Indo-Aryan)languages belong to the same family of "Indo-European Languages" and are very close or similar to each other. So the Europeans can easily learn the Indian languages and vice versa. [ But the inhabitants of Far-East and South-East Asian countries, find it difficult in learning the European and Indian languages, because the language-family of the former is quite different from that of the latter. ] Since the late 19th century A. D., the liberal-minded European great scholars studied thoroughly both European and Indian (or Indo-Æryan) languages by means of the modern Philological method comparing those languages with each other and wrote the various works or books on Sanskrit, Pali and other Prakrit languages, which served to know or understand those languages within a short time.
On the contrary, the traditionalist Venerable Sayadaws (abbots) in Asia, especially in Burma, spend a long time (longer than necessary) on learning Pali by the traditional (outdated) method through the traditional Pali grammars (such as the Kaccayana, Rupasiddhi, Moggalana, Saddaniti, Bhedacinta and so on), which give illogical or unsystematic (sometimes wrong) explanation of Pali words, using the grammatical suttas, scattering here and there, but they never become skilful or expert in the real or systematic formation of Pali words and are unable to decide the Pali words-"which one is correct and which one is wrong", and "which one is original (primary) form and which one is secondary form".
So, let me say frankly "It is the best way to learn Pali language by means of the time-saving modern (updated) method of philology, a comparative study of Pali with Sanskrit and Prakrit languages, so that one can become, within a short time, an expert not only in Pali but in other Indian languages (Sanskrit and Prakrits) as well". For, the world-conditions are ever changing, the world seems to be as small as a village, due to the rapid progress in commutation and there are too many things to be learnt within a very short life-span. Moreover, it is the greatest mistake that the extreme traditionalist venerable Sayadaws (abbots) of Burma do not allow their pupil monks to study Sanskrit and English, and as a result most of the Burmese monks become backward in the worldly and religious matters, not knowing and not willing to take part in the missionary activities both at home and abroad. So, it is high time to urgently change, modernize or improve our traditional (outdated) monastic education (Pariyatti learning) to reach the international standard, in accordance with the ever-changing world situations.