Proxy Contracts - ERC1967Proxy, Transparent and UUPS explained.
In-depth explanation.
pv
Solidity Storage - Slots and layout
In depth explanation of solidity storage and layout starting from the basics of hexadecimal.
EVM - Init and Runtime code
In-depth explanation.
Ethernaut - GakeKeeperOne walkthrough (Finding gas using the debug method)
Solution of this brainfuck level
Solidity Attacks => Re-Entrancy
Re-entrancy attack explained
Solidity - Endianess and Bytes explained
In depth-overview
Solidity notes
Just a few important terms
Solidity - Receive and Fallback functions
Low level overview of these functions.