What is the meaning behind this chant?

Who are the eight [types of] individuals that the chant refers to, and what is the meaning of the chant? Apparently, it is the Wat Phra Ratana Mahathat Monks at evening service before the great bronze Chinnaret Buddha, Phitsanulok Thailand. Source: Freesound The translation came from the YouTube comments section but I cannot locate it any longer. Here is the link to a looped version... Buddhist Chanting > Of good conduct is the Order of the Disciples of the Blessed One. Of upright conduct is the Order of the Disciples of the Blessed One. Of wise conduct is the Order of the Disciples of the Blessed One. Of proper conduct is the Order of the Disciples of the Blessed One. > This Order of the Disciples of the Blessed One, namely these Four Pairs of persons, the eight [types of] individuals, is worthy of gifts, worthy of hospitality, worthy of offerings, worthy of reverential salutation, and is an incomparable field of merit for the World. --- > Supatipanno Bhagavato sāvakasangho Ujupatipanno Bhagavato sāvakasangho Ñāyapatipanno Bhagavato sāvakasangho Sāmīcipatipanno Bhagavato sāvakasangho > Yadidam cattāri purisa yugāni Attha purisa puggalā Esa Bhagavato sāvakasangho Āhuneyyo Pāhuneyyo Dakkhineyyo Añjalīkaranīyo Anuttaram Puññak khettam lokassāti