Hello world! I'm talking about converting hexadecimal to binary numbers. T convert a number from hexadecimal to binary we simply replace each hexadecimal digit with four binary digits. Here I have the hexadecimal number F0A3. and three would be 0011 A is 1010. For the 0, it's important that you put four zeroes: 0000. Each of those is placeholder: we have to put all of them. then we have F is 1111. And we could write this number F0A3 in base 16 equals this number in the base 2. Let's do one more. Pause your video and try it, when you're ready restart the video. For F we have 1111 and for 0 we have 1, 2, 3, 4, zeroes. C is 1100 9 is 1001 and 4 is 0100. and you can leave off that beginning 0 if you want to. Again, we're going to write this is the base 16 and is equal to this number in base 2. And that's it.