"...that is similar to your mark and used on related products or for related services." That is directly from the USPTO. In other words, if you have a company

"...that is similar to your mark and used on related products or for related services." That is directly from the USPTO. In other words, if you have a company named "A" that writes software and I have a company name "A" that makes shoes.. I can't sue you for trademark infringement. A website doesn't matter.. it's the type of business that matters.