Function names consist of several descriptive words, concatenated into a single word-description of the function. To help you remember the names, they are constructed within a prefix/verb/noun model, where:
The prefix "tapi" indicates that the function belongs to Simple Telephony API. The prefix "line" or "phone" indicates that the function belongs to the Full Telephony API. "line" prefixed operations work on the connection to the network. "phone" prefixed operations work on a telephone set. This is a phone-type device that is somehow associated with the PC running the application, and controlled via the API. The mechanism used to establish the actual association is up to the different implementations. Function prefixes are always written in lowercase.
The verb tells you what the function does. Function verbs always begin with an uppercase letter.
The noun describes the target of the action. The noun may be absent in cases where the verb makes it obvious what the noun should be. For example: lineAnswer is used instead of the longer lineAnswerCall. Conversely, some function names contain more than one word for the "noun". Function nouns, like verbs, always begin with an uppercase letter.
As an example of a function name, lineMakeCall is a line function that establishes a phone call.