a bot is a computer program which can be written to do whatever you want on betfair. It can place bets, cancel bets, trade, download prices etc.... all at speeds much, much faster than a human could ever manage. You can set it to place/cancel a bet when certain conditions happen (odds, amount of money waiting etc).
The computer program uses the betfair API to connect, and depending on how often, for example, you download data you might incur some additional charges. There is a free API, but it restricts how often you can access the site.
a bot is a computer program which can be written to do whatever you want on betfair. It can place bets, cancel bets, trade, download prices etc.... all at speeds much, much faster than a human could ever manage. You can set it to place/cancel a bet