Can anyone give me a 10,000 foot high level summary of what crypto currency is?
Why do we actually need crypto currency? What is this technology? Like why is it not just digital cash (meaning it’s same as every other currency but not available in physical format)?
Bitcoin was created to answer the 2008 financial crisis where banks ripped off the people giving them sub-prime loans. It's a de-centralized (no banks) currency where transactions are saved on the blocks, hence blockchain technology.
Why are there so many different ones?
They're now using the blockchain technology from bitcoin to create several different other coins with different purposes. Monero is a cryptocurrency that is completely private and anonymous. Factom is trying to be a universal record keeper of the world as documents are kept on the block and are secure/private. Sia lets you rent out hard-drive space for $, like storage. Civic gives everyone a digital identity, no need for IDs, passport etc. Some coins are better or worse versions of the ones mentioned above, and there are many other practical uses.
Is lots of research and $100 a month enough to get into this or am I better off not learning and investing if my funds are that low?
100$/month is fine, only invest what you're willing to lose. Keep in mind crypto is hyper-volatile, can dip 50% in a day, or go up 1000% another.
