pure for functions: Disallows modification or access of state.view for functions: Disallows modification of state.payable for functions: Allows them to receive Ether together with a call.
constant for state variables: Disallows assignment (except initialisation), does not occupy storage slot.immutable for state variables: Allows exactly one assignment at construction time and is constant afterwards. Is stored in code.anonymous for events: Does not store event signature as topic.indexed for event parameters: Stores the parameter as topic.virtual for functions and modifiers: Allows the function’s or modifier’s behaviour to be changed in derived contracts.override: States that this function, modifier or public state variable changes the behaviour of a function or modifier in a base contract.