Loving Kindness Mediation

Buddhist tradition recommends 4 meditation practices

1. Metta (loving-kindness)
2. Karuna (compassion)
3. Mudita (appreciative joy)
4. Uppekha (equanimity)

I’m not sure what to make of this company, yet
https://positivepsychology.com/

The resources about the loving-kindness meditation seem worth a second look.
Does anyone have any experience or advice

https://positivepsychology.com/loving-kindness-meditation