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Everybody what's going on this is Caleb with Dev's Loeb's dotcom.

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And in this video we're going to be talking about variables and their storage capacity in programming.

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Memory management is super important.

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Thankfully most of this is done for us which is really cool but there are circumstances where we might

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have a need for a specific type or size of data.

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OK so that's where this storage capacity and variable size is going to come into play.

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So let's dive right in.

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The first thing we need to consider is device architecture.

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Okay.

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Now that means does the you have an 8 16 32 or 64 bit processor.

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I'm sure you've heard those words before.

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Like you know your computer might have a 64 bit processor.

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A basic understanding of binary will help us understand the capacity of variables for these different

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architectures.

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OK.

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Now in binary bytes are arranged in 8 bit chunks with the value of each bit being worth double its neighbor

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going from right to left.

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K. now a processor that can handle 8 bit chunks of data is called well an 8 bit processor.

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Ok.

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Popular computers that utilize this long long time ago were the apple one the apple to the Atari 2600

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and even yes the Nintendo Entertainment System.

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So it's it's been around it's been a popular thing now 16 bit processors.

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They came along and they were faster and able to handle bigger chunks of data at the same time double

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the capacity of its predecessor.

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Pretty impressive for a long time.

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Our computers and devices ran on 32 bit processors but eventually they made a jump up to 64 bits which

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is what most computers nowadays utilize and devices as well like my iPhone for instance has a 64 bit

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processor.

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Now when you start thinking about the capacity of an 8 bit system that means that the largest possible

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value for a particular chunk of information is 255.

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As we add up all the values of the 8 channels we get 255.

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However when we double the capacity to 16 bits we're suddenly able to store up to sixty five thousand

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five hundred thirty four 32 bits gets us four billion two hundred ninety four million nine hundred sixty

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seven thousand two hundred ninety four.

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So you can see the exponential growth here and 64 bits gets us up to over 18 quadrillion.

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It's insane how big the capacity becomes with 64 bits.

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So now that we know the size of the chunks of data that RCP can handle Let's talk about variables in

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programming a variable is a value that is stored in memory and used and modified by a program.

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There are different types of variables as well integer values.

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Decimal values text values and boolean values like.

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True or false.

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So as an example let's look at some very specific integer types unsigned and signed integers.

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So in many languages you can use unsigned unsigned integers unsigned just means that a value can either

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be positive or 0 signed means that the value can be positive negative or zero unsigned integers have

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a storage capacity of 8 16 32 and 64 bits you can make an unsigned integer with any of those bit sizes.

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And believe it or not that means that for whatever size they are they can store a max value of the sum

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of their channels k.

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So basically what I mean is like an 8 bit unsigned integer can hold a value of 255 16 bit can hold sixty

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five thousand five hundred thirty four and so on.

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Just like the values we talked about before with with the processors can handle those sizes of chunks

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of data the various integers can also hold those chunks of data.

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Now a signed integer since it can be both positive or negative.

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We basically take it's total capacity and cut it in half.

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And so basically it has an equal reach for both positive and negative.

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So where a 16 bit unsigned integer can go from 0 up to five thousand a signed 16 bit integer can go

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all the way up to thirty two thousand seven hundred sixty seven and all the way down to negative thirty

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two thousand seven hundred sixty seven.

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So we just cut that number in half decimal values can be represented by either a double or a float.

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In most programming languages and usually a double has a 64 bit capacity and is more precise you know

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more data equals more precision.

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A float has a 32 bit capacity and both both are accurate but a float has slightly less that because

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it can hold less data.

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Now let's move on to another type of variable called a string and a string holds text data.

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OK.

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And depending on the architecture of your device it can hold either 32 bits or 64 bits worth of data.

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That's a lot of data for one string.

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So that's actually way more than you would usually ever use.

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Most strings are going to be nowhere near that that large and they shouldn't be because that's just

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ridiculous.

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You should probably find another way to show text data if you are trying to hold Sixty-Four entire bits

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of information.

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That's insane.

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So anyway it's cool to know.

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So to recap we talked about processors and the different sized chunks that they can handle in data depending

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on their architecture.

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8 bits 16 bits 32 bits or 64 bits.

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We also talked about variables and their various size capacities like unsigned unsigned integers like

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strings like doubles and floats.

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And we even talked about the various variable types.

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Right we talked about what they are.

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String is for holding text a boolean is for holding a true or false value.

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A double is for holding a decimal value with with a greater accuracy than its neighbor the float.

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We talked about all of that amazing work.

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And let's head over to the next video and let's continue learning.

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This is Caleb with devs Loeb's dotcom.