A period is a single small dot at the end of a group of words that have been written and it means that this is the end of a complete statement or sentence.

The period is a warning to the reader that the statement is finished and so it must not be run together with whatever follows it.

The idea that is stated in the sentence, or group of words, begins with a capital letter and ends with a period which is presented in the form of a simple assertion.

The writer does not intend to ask the reader a question, nor does he or she want the reader to feel that the sentence is expressing a thought with great emphasis. It is simply stated and that's what the period tells readers.

That is all anyone needs to know about the single little dot which is used as a mark of punctuation and is called a period. Oh, yes, remember that when an abbreviation occurs at the end of a sentence, or a statement, the abbreviation point and the period are combined into one dot and so the use of two dots is not necessary nor acceptable in normal English writing.

Fat little period, round as a ball,
You'd think it would roll,
But it doesn't
At all. Where it stops,
There it plops,
There it stubbornly stays,
At the end of a sentence
For days and days.

"Get out of my way!"
Cries the sentence. "Beware!"
But the period seems not to hear or to care.
Like a stone in the road,
It won't budge, it won't bend.
If it spoke, it would say to a sentence,
"The end."