Simple Ledger Protocol (SLP)

Basics

Launched 8-2018. In 12-2019 there are more than 6,000 SLP tokens in existence and a number of SLP tokens have seen price discovery. The total market cap surpasses $50M.
A simple open source token system for Bitcoin Cash. It will allow tokens to be created on BCH.
"No Native Token Some token protocols have their own coin which you must first acquire in order to use other tokens. SLP runs directly on top of BCH."
Scriptable; You can use multi signature addresses and other Bitcoin script features with SLP tokens.
On the question of if SLP is like Ethereum’s ERC-20, but for BCH?:

"In many ways, yes. Anyone can issue, or “mint” a new token type. Tokens can be traded, spent, or given to someone else. They operate in a distributed manner like most cryptocurrencies. Custom token behavior can be added using bitcoin Script programming language in novel ways."

In a nutshell, how does SLP work technically?

"You can think of SLP as a ‘transaction within a transaction’. SLP transactions live within a special output known as OP_RETURN, which is a part of a standard Bitcoin Cash transaction. If Alice wants to send Bob some tokens, she sends a minimal (dust) amount of BCH, and the transaction also contains the data to transfer the tokens."

Postage Protocol

From this Medium article by Vin Armani (18-11-2019):

"In order to move SLP tokens, a user needs to have a small amount of additional BCH available to their wallet to pay miner fees. It’s the “gas” problem all over again. At least that was the case until the publication of the Simple Ledger Postage Protocol as an official SLP specification. The stated purpose of the new protocol specification is:

“…[For] the sender of SLP tokens to effectuate a transaction without the need for additional native Bitcoin Cash (BCH) inputs to cover output balance and/or miner fees. Use of this protocol enables wallets to exclusively support SLP tokens without also, simultaneously, having to act as a wallet for native BCH.”

In essence, the Postage Protocol allows users to pay for their miner fees using the SLP token itself. This is accomplished through the use of an intermediary server called a “post office.” The user sends the post office the requisite value of the needed BCH as an additional output in a transaction. Upon receiving and validating the otherwise invalid transaction, the post office attaches additional input containing native BCH (“stamps”) and then broadcasts the “postage paid” (valid) transaction to the network. This is accomplished leveraging fundamental Bitcoin transaction capabilities along with functionality already used with BIP-70 and the Simple Ledger Payment Protocol. In fact, existing BIP-70 servers and supporting merchants can provide postage services for buyers. The goal is to see a competitive marketplace with post offices supporting all major SLP tokens and working to provide the lowest price and highest quality for postage services. CoinText is offering the first post office. It is currently live and supports HonestCoin (USDH), Spice Token (SPICE) and Anypay Gold (GOLD)."

Creators

According to CoinSpice ("for all intents and purposes, appears to be, the fathers of SLP")