In the NFL, 10 yards are needed for a first down, but penalties and plays can affect it.
You have to get a first down. When you get a first down, it moves the chains and it is first down. When you have a first down and the are no penalties, it is a first and ten.
On a start of a possession with out any penalties it is 10 yards long.
Only if the penalty yards are greater than the yards needed for a first down.
1994. Brazil beat Italy on penalties.
If there are no penalties the yardage needed is ten (10). Penalties on either offense of defense can alter the number of yards needed but the standard is ten. For example, if a first down is initiated at the 20 yard line and your team is going towards the other team's goal (to score), your team would need to get to the 30 to get another first down. Your team would have 4 downs to accomplish this but often use the 4th down to punt the ball to the other team. The scenario just described does not include penalties which can award an automatic first down or set your team back any number of yards depending on the penalty.
3rd and 10 would usually refer to Third down and 10 yards to go to get a first down. 1st and 30 would usually refer to First down and 30 yards to go to get a first down. 1st and 30 would only happen if there were a penalties on the offense that moved them 20 yards back, could be a combination of penalties.
The Steelers had 4 penalties for 32 yards in the first half of Super Bowl XLV.