​​What do Red and Yellow cards in Soccer mean?

The Yellow card is a caution, given for offences such as Unsportsmanlike conduct, breaking up a promising attack (BUPA), dissent, delaying the restart of play, and entering/leaving the field of play without permission.
The Red card is a send off, so the player must leave the field, and cannot be replaced. It is given for offences such as Serious foul play, violent conduct, Denial of an Obvious Goal Scoring Opportunity (DOSGO), Abusive language, and recieving a second caution.