I was watching Netflix Narcos and noticed that the word plata was used dominantly to refer to money instead of dinero. The translation for the former would be silver. Is this difference a result of advancement in language? Is that word still applied in modern usage?
Plata, which literally means "silver", is also one of the most common ways to refer to money (in any form) in American dialects of Spanish. As in English, there are many other ways to call money or certain amounts of money (as in luca for "one thousand currenty units"). I'm not aware of those other names being used in Narcos.
Dinero is the "proper" designation for money, but the word is almost unheard of in colloquial language (again, in American Spanish); in some places it may even sound too formal except for, well, formal occasions. So both dinero and plata are current and perfectly good words for "money", but plata is to be preferred.
According to the entry in the dictionary of the Royal Academy for plata_
- f. Am. Dinero o riqueza. No tengo plata para comprar.
So they classify it is an American usage. I assume from web searches that Netflix Narcos is primarily set in Colombia.
plata is a slang for money in many Latinamerican countries as Mexico, Colombia, Venezuela or Argentina. Not commonly used in Spain. However you have several of slangs per region in Spain to speak about money as: pasta, perras, perres, pelas, etc...
Dinero as a word for money is as well commonly used in many day-to-day formal or informal contexts, in Spain and all around the spanish-speaker world.