Wesley1982 wrote:... a buddhist monastic community with formal ordinations and have taken the vows...
In English, those are typically called 'Monasteries'.
A sangha is simply a community of practicing Buddhists, often led by a spiritual 'master ' who may have been formally 'ordained'.
As to whether or not this 'electronic forum' qualifies as a sangha, you will likely find widely differing opinions.
The others are the Buddha and the Dharma.