A) "Too long; didn't read.", meaning a post, article, or anything with words was too long, and whoever used the phrase didn't read it for that reason.

B) Also used by someone who wrote a large posts/article/whatever to show a brief summary of their post as it might be too long.
a)
Guy One: Did you read that book for English class?

Guy two: No, tl;dr.

B)
Guy one: Cake is a form of food that is usually sweet and often baked. Cakes normally combine some kind of flour, a sweetening agent (commonly sugar), a binding agent (generally egg, though gluten or starch are often used by vegetarians and vegans), fats (usually butter, shortening, or margarine, although a fruit purée such as applesauce is sometimes substituted to avoid using fat), a liquid (milk, water or fruit juice), flavors and some form of leavening agent (such as yeast or baking powder), though many cakes lack these ingredients and instead rely on air bubbles in the dough to expand and cause the cake to rise. Cake is often frosted with buttercream or marzipan, and finished with piped borders and crystallized fruit.1

Cake is often the dessert of choice for meals at ceremonial occasions, particularly weddings, anniversaries and birthdays. There are literally millions of cake recipes (some are bread-like and some rich and elaborate) and many are centuries old. Cake making is no longer a complicated procedure; while at one time considerable labor went into cake making (particularly the whisking of egg foams), baking equipment and directions have been simplified that even the most amateur cook may bake a cake.

tl;dr: Cake is a baked, yummy sweet.
by Soonmme July 15, 2008
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Too Long; Didn't Read

Used in reply to a post and/or comment or other written material that dragged on way too long about things that weren't very important.

Also sometimes used by trolls on posts that are longer than their attention span, or in an argument or flame war when one person can't come up with a comeback.

Also usable on your own lengthy post at the end followed by a quick summary of the above material as a courtesy to people who might not want to read the entire thing. Essentially the same as writing "In Summary," when used this way
1. Guy #1: Did you read that book for english class yet? I'm still on page 537.
Guy #2: tl;dr. The book is mostly made of random extraneous details. I bought the study notes instead, they were only 50 pages long.

2. Troll: lulz ur such a fag
SomeGuy1: It really is pathetic that you would make accusations about my sexuality instead of coming up with a legitimate argument. I wonder if you even watched the video before posting.
Troll: tl;dr LOL
SomeGuy1: How old are you, 5?

3. (lengthy post)
tl;dr, Cats are awesome.
by TheAbyss May 8, 2012
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tl;dr : Too long, didn't read.
"Did you read the fourth definition, it was quite witty!"
"no tl;dr"
by Aleksei Nikolaevich Tolstoi November 17, 2007
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Literally, "Too long; didn't read"

Said whenever a nerd makes a post that is too long to bother reading.
"omg you postwench. i can only say one thing in response - tl;dr"
"tl;dr...why dont you give up on your unabridged edition of War and Peace or at least stop posting it here?"
by DisgruntledJoe November 21, 2003
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Too long ; Didn't read.

Any over wordy thread or long drawn out story that people don't want to really read, but reply to anyway.

Also a form of trolling or humorous reply telling some one to get to the point.
by D. ESPI March 13, 2003
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too long, didn't read
most often used in forums, when someone writs a really long post
tl, dr. that was a freaking essay.
by Carmen March 23, 2004
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A very complicated acronym
Its definition is so long no one reads it
"Did you find out the definition of TL-DR?"
"Too long. Didn't read."
by Michail Borisovič Rusakov August 1, 2019
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