 In this video, we're going to look at the basics of algebra, focusing on the notation that is used. Whilst we will quickly look at why we use algebra, I am going to assume that you have met it a little bit before. In algebra, we use symbols to represent numbers. These are usually letters. The symbols are called variables. Calculating symbols instead of numbers is great because they may sometimes represent long numbers and so it saves us having to write them out every time. Like pi, which is 3.14159 and so on, which makes calculating much easier. Instead of writing out the whole numbers every time, we can just say a multiplied by b instead, much easier. A big reason for using symbols instead of numbers is that the symbols or variables can represent unknown quantities and for showing formulae like the area of a circle. So let's have a look at some of the key notation. Adding and subtracting stays the same but instead of writing the multiplication sign, we can remove it and just write a b instead. So if you ever see two letters next to each other or a number and a letter, then it just means to multiply those things together. Notice how we always use a curly x for the letter x because otherwise it would look like a multiplication sign so make sure your x is a curly. So that's adding, subtracting and multiplying. Instead of the division sign, in algebra, we usually write it as a fraction and then we still use everything else that you've probably come across in arithmetic. Another great habit to get into is to leave numbers as fractions rather than decimals, so 3 eighths a rather than 0.375a. From that note, these mean the exact same thing. You can write it whichever way you prefer. So there's an introduction to basic algebraic practises. Remember to always use a curly x that we don't really use a multiplication sign and that we usually write things as fractions rather than using the division sign.