By itself, a computer language consists of several things: built-in types of data like numbers (integers and floats), letters (characters) and ordered lists of these data types (arrays). It also provides simple tools for working with this data (keywords and operators) as well a rules for organizing the data, keywords and operators together to instruct a computer to do something (syntax). Combining data and instructions under a syntax provides a programmer with endless possibilities for writing applications, games, nearly anything. However, that which is possible is not necessarily practical.
Application Programming Advantages
Application Programming Interfaces (APIs) provide software developers with advantages. Rather than focusing on unnecessary and tedious details, the developer can focus on constructing their vision. For example, if the developer need to take the square root of a number, it would take approximately one hundred lines to determine a square root. Fortunately, in addition to the data types, operators, keywords and syntax, nearly all languages provide a set of APIs (or libraries) to prevent re-implementing the same basic needs. A developer can simply write ‘sqrt(25)’ rather than writing the hundred lines necessary towards calculating the square root of twenty-five.
Not only do languages provide basic Application Programming Interfaces (such as C++’s Standard Template Library or Java’s Runtime Library) to simplify core work, but third parties provide them for more complex and specialized work, such as rendering graphics for games or talking with other programs over the network. Often, development firms sell specialized APIs for a premium price. However, through open source projects like Apache and GNU, many of the best APIs are provided for free with the source code available to be read and modified by the user.
In short, an Application Programming Interface is a library of tools to enable software developers to spend less time focusing on tedious and incidental detail of solving problems that have already been solved (while introducing bugs in the process) and instead innovate new software.
If Application Programming Interfaces are of interest to you, you may want to pursue a degree in data science.