Thomas was not drafted but signed as a free agent linebacker with the Saints, who cut him during training camp. He was later picked up by the Oakland Raiders, who also cut him.
Each NFL team is allowed up to eight practice squad players, who are considered developmental players. They practice with the team but are not activated for games unless done so in a separate transaction.
They are paid on a weekly basis, at a minimum of $6,000 a week, and can be cut at any time. When they are signed, they receive a minimum of three weekly payments, even if they are released before that period ends.
Here's more on Thomas' prospects with the Falcons, who have lost several key defensive players just two games into the season.
The latest is starting linebacker Sean Weatherspoon, who will be out at least eight weeks with a foot injury.