A String Identifier (SID) is a unique key that is used to identify specific resources.
Every Twilio resource has a 34 digit SID. You can use the first two characters of the SID to identify its type. Many of our API calls will return a JSON object containing another resource's SID. Using this SID, you can retrieve more information about the specific resource.
For example, the following code creates an SMS message:
Note how the newly created message has a property named
sid. Using this value we can later fetch this specific message.
Using the message SID, which is prefixed with
MM, we were able to get more information about that specific resource.
Below is a table of the most commonly-seen SID prefixes: