The way you access an API is basically via URL (that is to say, the address you enter into your browser to access a webpage), albeit a slightly more unique version. In the URL you will have to enter a specific program you want to access, for example, you will have to indicate that you want to access a verb conjugator. But for the program to work, you will need to provide certain details. In the case of the verb conjugator, you will need to give the infinitive verb you wish to conjugate. These details that have to be entered into the program are called parameters, which are also included in the URL (later on you will see how this works). In other words, with the verb conjugator, the parameter will be an infinitive.
Therefore, in order to call an API you will need:
– The URL to access a specific program.
– The necessary parameters (which vary according to which program you want to access).
Just using these few details, you will be able to attain a wide range of APIs. However, you will normally be asked to provide some more information. The majority of the APIs require the user to present an authorisation key before they can call an API. That is, the programmer who has submitted the API will ask anyone wishing to connect with their program to register with the system. This is so that the owner of the API can regulate the number of people using their API, and will also be able to limit the number of times (per minute, per day, per month) a specific user can access the API. This method is useful in two aspects. First of all, the creator of the API can ensure that their application does not become a victim of its own success from receiving various requests and not being able to manage them all at once, which would then prevent it from working properly. Additionally, if the owner of the API wants to commericalise it, they will display tarifs according to the number of times a specific user has consulted the API, and so the owner will need to identify every user to determine how many times the API has been used and to be able to charge them a fee.
Therefore, to be able to use the majority of our APIs, you will need an identification code which is provided by the programmer of the API. When you access the API, you will have to enter this code (as well as the URL and parameters required) so that the owner of the API knows who you are, and then you will be allowed to consult the API.