You can't have a complete sentence without punctuation, and, luckily, punctuation rules are very similar in both Spanish and English. On the basic level, a period is used at the end of a sentence, and a comma is used for the same reasons you would use a comma in English. However, there are some differences between Spanish and English.
One unusual punctuation mark is the upside‐down question mark (¿) that precedes a Spanish question. The question is followed by the same question mark (?) used in English. Because Spanish questions often look exactly like sentences, the upside‐down question mark is necessary to identify that what follows is a question.
The upside‐down exclamation point (¡) is another unusual punctuation mark. It precedes a Spanish exclamatory sentence and is followed by the same exclamation point (!) used in English. The emphasis indicated by an exclamation point at the end of the sentence is reinforced by an upside‐down exclamation point at the beginning so that the reader knows to say the sentence with emotion before the sentence is over.
Punctuation and numbers
There is a rather confusing aspect of punctuation that occurs only with numbers. The Spanish use a comma to indicate a decimal point and a period where we use a comma in numbers. For example: