What bots are really worth letting onto your site?

[Shirley_Sharp]

I have known about a number of bots such as Google, Bing, Yahoo, Alexa bots, and seen the massive amounts of random bots that happen to crawl a site, I could knot know all, what bots are really worth letting onto my site? How to detect and filter them?
My first thought is that allowing bots that will help my site increase crawl rates or SEO scores on search engines. Is there any reason to allow bots or stopping them from visiting a site?

 

[Elegant_Designs]

Bots from Google, Bing, Yahoo and from other reputable search engines or sites such as Alexa are okay

If unknown bots are wasting resources on your website by crawling your web pages over and over again within a short period of time, it is best to block them. Some bots appearing on your analytics are just there to entice you to visit their website and usually their bounce rates are pretty high which will affect your analytics data; you should filter them out from you Google Analytics to have a cleaner data.