According to the Algorand Developer Portal, “Algorand Smart Contracts (ASC1) are small programs that serve various functions on the blockchain and operate on layer-1.”  Similarly, according to Vitalik Buterin, “systems which automatically move digital assets according to arbitrary pre-specified rules.”  The former MIT professor and current Commissioner of the SEC, Gary Gensler, states, “A set of promises, specified in digital form, including protocols within which the parties perform on these promises.” 
Retired Algorand Contracts
Stateful and stateless smart contracts are two retired types of Algorand smart contracts because they are no longer used and considered widely outdated. In fact, there is nothing contractual about their logical nature. Moreover, both Stateless and Stateful Smart Contracts lack the ability to be written as a single script executable for basic digital asset transactions. Thus, Stateful and Stateless have essentially been retired to the archives because they failed to achieve any significant transactional function and were highly susceptible to hacks.
Algogeneous Smart Contracts
More recently, Choice Coin — the premier open source software project on Algorand — developed Algogeneous Smart Contracts, which represent a technical convergence of Stateless and Stateful Smart Contracts and include an innovative integration with artificial intelligence. Algogeneous Smart Contracts are the new generation in both transactional and computable smart contracts on the Algorand Network. Additionally, they are the most popular type of smart contract in use on Algorand because they are the only type of smart contract to allow multiple tasks to be efficiently characterized in a single function. Simplex sigillum veri.
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