Coins that have the real name "penny" (as opposed to the US/Canadian slang term for a cent) have been issued by many countries in the British Commonwealth / Empire.
If will almost certainly have a picture of the British monarch on it. If no country name is shown, it's from the UK. In that case, if it's about the size of a US nickel it's a modern penny worth face value only. If it's about the size of a US half dollar it's a so-called "old penny" whose value depends on its date.
Most other countries in the Commonwealth converted to dollars and cents back in the 1960s or 1970s so if your coin has a country name on it (e.g. Australia or New Zealand) it's from a date before conversion. Again, its value would depend on date and condition as well as the issuing country.
Please post a new, separate question with the coin's country of origin. If it says ONE CENT, it's a US Large Cent. If it says ONE PENNY, it's a British penny.
The 1881 one penny coin can be worth from $6.00 to $50.00 depending on the condition of the one penny coin.
The coin that is not a penny is a quarter. The other one IS a penny.
coin penny 1988 one penny
It is a Patriotic Civil War token, rarity R2.
A penny is a unit if currency (money), thus one penny means one unit/coin of this currency (1p).
lol im wasting the answer ahahahahahhahaha but i have the same coin
No US one cent coin struck in Philadelphia has ever had a "P" Mintmark so the coin is just a penny.
"A penny" isn't an idiom - it's just a one-cent American coin.
one cent
The rarest British Penny would be the 1954 Penny. There is one known to exist, maybe two, but there could be some doubt about the second.
That would be a coin of the Irish pound, which has since been replaced by the euro.