The basic primordial beej mantra is “om”, it's the mantra from which all one other mantras ended up born. Every beej mantra has a certain god or goddess linked to them. The categories of beej mantras are— Yog beej mantra, Tejo beej mantra, Shanti beej mantra, and Raksha beej mantra. https://conrads863qwz7.ssnblog.com/26399749/beej-mantra-an-overview