The broker in its original sense could be thought of someone that you phoned in order to buy or sell currencies. The development of the Internet and software now allows you to interact with a broker through what is called a trading platform or trading software.
A trading platform is a piece of software and it is through this software that you actually buy and sell different currencies. Trading platforms are software downloaded from the Internet and installed onto your computer. This is what you use to trade forex. However, there are forex brokers that actually enable you to trade through a web browser, which can be beneficial as it allows you to trade from any computer without having to download software.
Similarly, imagine you are now selling apples and need to find customers; you can go to the street market because that is where your customers are – that is where there are people buying apples.
The street market is a place where buyers and sellers meet. However, when you go to a street market, you do not generally see many people selling apples to each other; they will be sold through a stall.
In the forex markets, this is no different. You have buyers and sellers of different currencies – they need a place to come together and there needs to be a facility to actually buy and sell those currencies.
In the forex markets, however, the buyers and sellers can be thousands of miles apart. In order to find each other, there must be a mechanism that matches their interests: this is where the broker comes in.