Sahih Al-Bukhari: introduction

This introduces Sahih Al-Bukhari. "Isnad" is the word I was failing to remember. Isnad is the chain of narrators of hadith. In other words a named person, heard from another named person who heard it from another named person... who told it to the hadith compiler. I should have made it clearer that this is a Sunni hadith. I don't know of a Shia hadith. Tell me if there is a Shia hadith translated into English.