Hello @sapwood. I read your lecture and understand it now I am writing in own words.
What is Multichain wallet
The multichain wallet can be described as a wallet that enables users to store different cryptocurrency assets in one wallet.
As the number of public chains is increasing day by day, a single-chain wallet for every asset is difficult for users to operate. The multichain wallet is the solution to this problem, where a single wallet is used to store multiple assets of different public chains.
What is Trust Wallet
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This is a multi-coin wallet that binance originally did in 2018, providing it with the same account to send and store any kind of crypto currency exchange. It allows different COINS to support crypto currency such as bitcoin, ethereum, ethereum classic and binance coin also.
This wallet support more 160 k crypto assets and 40 blockchain. Written on the its own website.
How I backup seed key/Individual private keys
In Trust Wallet , This is easy step to backup seed key or individual private key.
Blow some screenshots to understan.
If you are new then install first trust wallet, Simply go to the playstore, search trust wallet and then install it.
You can create click on " create a new wallet " or if you have a wallet then click on " I already have a wallet".
Click on "Countinue"
Go to the setting icon and click.
Click on wallet.
Click right side on top corner.
You will show " Recovery Phrase ".
Importing of coin or Multichain wallet
If we install a new app then we have to use this option.
On Wallet, you can see plus sign (+) click on it to add.
Click now I have already a wallet.
Here you can see many wallet options. You can select and import by clicking on any wallet.
The next screen will be different for multi-chain wallet and specific cryptocurrency wallet. In case of Multichain wallet, only option available will be phrase. It can be 12 words or 24 words in some cases.
While for importing specific cryptocurrency wallet, 4 options will be available including phrase, private key and 2 other options. User can select any of these options and import wallet.