Jainism is basically a non-theistic ancient religion founded in India. It teaches non-violence, and respect for all living beings. Jains believe that salvation can be attained by perfection through successive lives. There are a small number of Jains who fast to the death. This practice is called santhara, and can be viewed as Jain extremism. Such devotees give up their physical existence, so they do not cause suffering to other beings. Though, it is not an illegal practice in India there are some controversies around it.
Jainism preaches that all souls are identical. Different organisms are bound by different karmas, so you should treat every living being with respect and kindness, and do not harm them. According to Jainism, to attain nirvana, one needs to liberate himself of bad karma, and remove all good karma as well. To explore the Jain philosophy, you can read books written by Subhadra Muni Ji Maharaj.
Jains go barefoot, carrying a small broom, so they do not crush any insects in their way. Many Jains put on a piece of cloth (muhapattis) over their mouth, so to avoid disturbing surrounding microorganisms in the air through the warm air of their breath.
As per the Digambara sect of Jainism there is no more Jain canon. The council of Pataliputra was held to accumulate the most significant Jain literature, but unfortunately it had failed. Previously Jain teachings or philosophy had been passed on through oral tradition. If you are interested in knowing more about Jainism, you can consider listening to the pravachan of Mahashraman Ji Maharaj.