Please advice what is the Bots and Spiders is? I'm a newbies here....
bots and spiders are special programs run by individuals or companies that visit your website for some purposes.
Some of them are "friendly", like googlebot that tries to index the content of your website, and some of them are not.
Like the ones, that extract email adresses to send spam to.
There are some other spambots, that are filling forms and this way are trying to "promote" some websites.
That's why most of the forms use the CAPTCHA (en.wikipedia.org/wiki/Captcha
Some of those bots can make many requests to your website, and make it load slower or very occasionally they may cause a server crash (Distributed Denial of Service Attack from many IP adresses).