pJar 0.99 is a combination of Sushiswap and Uniswap. This jars allow users to deposit their LP tokens and the rewards (SUSHI, BAS, MIS, etc) to be sold and reinvested into the LP tokens.
As suggested above, pJar 0.99 comes in different flavours. Depositing one of the above LP tokens returns corresponding pTOKENS.
Using the deposited LP tokens, pJar 0.99a, b, c, d and e receives and re-invests SUSHI rewards for you so that you end up having more LP tokens than you started out with. pJar 0.99f re-invests BAS (Basis Share) while pJar 0.99g re-invests MIS (Mithril Cash) pJar 0.99i is slightly unique, as you have to go to https://crv.ape.tax/ to get your yveCRV from CRV, then deposit it to sushiswap ETH/yveCRV and into the pJar.
Almost all of the pJar[x] tokens allow you to additionally earn PICKLE rewards by depositing them in the Farm.