Yes, it is available pretty much everywhere in first world locations, although there are third world places that lack internet of high speed, and this is sad.
I'm not sure of a specific number, however you can count on wireless being slower because it has to transfer the information packets from station to station. Therefore causing a delay, also security...
You can do faxing, calling, surfing, browsing and marketing in internet and even crimes. So many more you can do in internet. Example of calling and faxing is RingCentral services.