[AblemTee]

'Kathas', a corrupted spelling of the proper in Pali/Sanskrit, 'gatha', is twofold:
a. term for type of metered and often rhythmic poetic verse or a phrase. The word is originally derived from the Sanskrit/Prakrit root gai , which means, to speak, sing, recite or extol. Hence gatha can mean either speech, verse or a song."
b. denoting one part of the nine parts common to both of the Theravada and Mahayana Canons: the versified portion: gatha

In a nutshell:
1. The Buddhist Writ/Canon is threefold: Pali/Sanskrit: Ti/Tri-pitaka (Three Baskets)
a. Vinaya Pitaka: the Discipline Basket (Monastic Rules, Precepts and discipline related etc)
b. Sutta/Sutra Pitaka: the Discourse/Teaching Basket (*)
c. Abhi-dhamma/dharma Pitaka: the 'higher philosophical/scholastic analysis of the Teaching' or "that which exceeds and is distinguished from the Dhamma" Basket

(*) Pali/Sanskrit 'Sutta/Sutra'
a. Simplistically, it is the oral/written record of teachings/discourses attributed to the Buddha and His Disciples. Traditionally, it is believed to have been recited and complied at the First Council led chiefly by the Buddha's personal attendant and cousin, the Elder Ananda and having the signature opening of 'Thus Have I Heard'.

b. Scholastically...
i. when one uses the Pali term 'Sutta'...
a. it is in reference to the Discourses/Teachings as recorded in the Pali Canon, used & taught chiefly by the Theravada Tradition and anyone else who has an interest in it.
b. it has five 'Nikayas' (Pali/Sanskrit) or "collection", "assemblage", "class" or "group". They are:
Dīgha Nikāya, Majjhima Nikāya, Samyutta Nikāya, Anguttara Nikāya & Khuddaka Nikāya.

ii. when one uses the Sanskrit term 'Sutra'...
a. it is in reference to the Discourses/Teachings as recorded in the Sanskrit Canon (as found in the Chinese, Korean, Japanese & Tibetan versions/translations) used & taught chiefly by the Mahayana & its cousin Vajrayana Tradition and anyone else who has an interest in it.
b. it has a twofold part:
i. the first part is the collection of Discourses/Teachings from what is now defunct legacy of the 17-18 early Indian Buddhist Schools (of which Theravada managed to survive until the present day.) The Chinese Canon has the most collection of several schools whilst the Tibetan has the least. They are known as the 'Agamas' and are pre-Mahayana material.
- Main language is the sanskritised Prakrit and chiefly available in Chinese and Tibetan translations with ongoing and slow translations efforts into other vernacular languages, with limited availability online too.
- The Agamas has five parts: Dīrgha Āgama, Madhyama Āgama, Saṃyukta Āgama, Ekottara Āgama & Kṣudraka Āgama
- In comparative studies, the Nikayas and Agamas Discourses are often known as the near 'cousins' of each other in terms of content with very little minor differences.
- See a cursory comparison:
Nikayas: Dīgha Nikāya, Majjhima Nikāya, Samyutta Nikāya, Anguttara Nikāya & Khuddaka Nikāya.
Agamas: Dīrgha Āgama, Madhyama Āgama, Saṃyukta Āgama, Ekottara Āgama & Kṣudraka Āgama
(above order for both in English: long length, middle length, thematic linked, gradual/numbered & minor
-Another category of 'independent' collection of Agamic Discourses which do not fit into the standard fivefold scheme.

ii. the second part are the actual collection of Mahayana styled discourses, which some would classify in a simplistic manner of those having exoteric and esoteric themes: the exoteric ones where some of which have Agamas styled content but other than that its contents may differ in various proportions and themes. Some examples are the Wisdom Sutras collection, the Lotus Sutra, Flower Adornment, the Ratnakuta Sutra collection, the Mind/Buddha Nature/meditation based Collection like Lankavatara, Suramgama, Tathagatagarbha and etc.
Included also are Discourses which have esoteric flavour which includes mantra, tantra, visualization techniques, hand signs and so forth

c. As a short note here, (not meant to open another debate here) is that there are two prevailing views on this second part of the Mahayana Canon:
i. the traditional view by its adherents is that its origins are from the Buddha Himself as the 'continued higher teachings for the Bodhisattva Path'
ii. and the second opinion seems to suggest that they stem from affirmed realisations of Disciples and Masters on a Buddha's teaching and the term 'Buddhavacana' or word of the Buddha is not necessarily restricted to or constricted with sole reference to the prevailing dispensation of Sakyamuni Buddha, the Original Teacher and Founder in our world system but also Buddhas from other world systems, of which our world is only one.

Scholars today are still unable to determine the exactness and how the arising of the Mahayana came about to date although many educated opinions have been forwarded and equally many non-scholastic and sectarian ones have been around the Buddhist Community for centuries now. One source oft recommended to read on the matter would be this in the words of one online learned practitioner opined as an 'excellent, readable survey of Buddhist history and of the different schools. He does not color things through a particular doctrinal lens, which is what you'll find on most websites.' But it is out of print apparently unless one is willing to dig it via libraries or used bookstores. This is another option.

In closing remarks on 'Sutta':
http://www.accesstoinsight.org/tipit...7.03.hekh.html
82,000 Teachings from the Buddha
I have received;
2,000 more from his disciples;
Now, 84,000 are familiar to me. http://www.theravadabuddhism.org/quotesfromvenerables
The Suttas need to be studied, reflected on, and practiced in order to realize their true meaning. They are not meant to be ‘sacred scriptures’ which tell us what to believe. One should read them, listen to them, think about them, contemplate them, and investigate the present reality, the present experience with them. Then, and only then, can one insightfully know the Truth beyond words.

But it is easy to fall into a kind of ‘Pali fundamentalism’. The texts and language are so pure and precise that many of us who fall in love with the Nikāyas end up believing that they constitute the be-all and end-all of Buddhism. We religiously adhere to the finest distinction, the most subtle interpretation, based on a single word or phrase. We take for granted that here we have the original teaching, without considering the process by which these teachings have passed down to us. In our fervour, we neglect to wonder whether there might be another perspective on these Dhammas.

They are the answers given by teachers of old to the question: ‘What does Buddhism mean for us?’ Each succeeding generation must undertake the delicate task of hermeneutics, the re-acculturation of the Dhamma in time and place. And in our times, so different from those of any Buddhist era or culture of the past, we must find our own answers. Looked at from this perspective, the teachings of the schools offer us invaluable lessons, a wealth of precedent bequeathed us by our ancestors in faith.

Just as the great Theravādin commentator Buddhaghosa employed an encyclopaedic knowledge of the Nikāyas, many of the greatest ‘Mahāyāna’ scholars, such as Nāgārjuna, Vasubandhu, and Asaṅga, based themselves securely on the Āgamas. By following their example and making the effort to thoroughly learn these Teachings we can understand, practice, and propagate the living Dhamma for the sake of all sentient beings. Sources: 1 2 3 4 5 6 7 8 9