allows the operation of platforms that are built on blockchain to work and connect with the outside world.

Yes that's correct . Besides connecting blockchains with external world, oracles also connect blockchains with each other.

Decentralized oracles are secured and reliable, since they don't use a single point and also, they are almost impossible to manipulate.

Yes the independent nodes on which decentralised oracles operate are autonomous and have noneditable operating system free of central censorship.

information to work both ways, meaning it can send and receive data at the same time, it works for both sides.

Yes it is contrary to inbound and outbound oracles which only recieve and send information.

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