The exchanging and sharing information within two parties without the third person is called Peer to Peer or People to People. Basically, in p2p platform, the exchange of bitcoin involves in sellers and buyers with terms and conditions in the website.
The trading is done online, thus, Seller can decide own price of the bitcoin and what kind of payment acceptable. The buyers can easily search the sellers, according to the location, regarding the price of the bitcoin. They can conduct their own deal without the inter-mediated person.
According to my experience, Airfio is the best exchange platform to trade BTC to INR and vice versa. To be honest, the UI, the complete transaction process, is soo simple and easy that even a beginner in crypto space can trade easily.
Now, coming to the security. Airfio is one of the most secure and reliable platforms to exchange, with a quick and seamless transaction.