Solana contains a small handful of builtin programs, which are required to run validator nodes. Unlike third-party programs, the builtin programs are part of the validator implementation and can be upgraded as part of cluster upgrades. Upgrades may occur to add features, fix bugs, or improve performance. Interface changes to individual instructions should rarely, if ever, occur. Instead, when change is needed, new instructions are added and previous ones are marked deprecated. Apps can upgrade on their own timeline without concern of breakages across upgrades.
The builtin programs include the System, Config, Stake, Vote, and BPFLoader programs. For each, we provide the program ID and describe each supported instruction. A transaction can mix and match instructions from different programs, as well include instructions from third-party programs.
Create accounts and transfer lamports between them
Add configuration data to the chain and the list of public keys that are permitted to modify it
Unlike the other programs, the Config program does not define any individual instructions. It has just one implicit instruction, a "store" instruction. Its instruction data is a set of keys that gate access to the account, and the data to store in it.
Create stake accounts and delegate it to validators
Create vote accounts and vote on blocks
Add programs to the chain.
The BPF Loader marks itself as its "owner" of the executable account it creates to store your program. When a user invokes an instruction via a program ID, the Solana runtime will load both your executable account and its owner, the BPF Loader. The runtime then passes your program to the BPF Loader to process the instruction.