The classical Latin alphabet is a special way that people who speak Latin (an old language mostly used in ancient Rome) write down their words. The alphabet has 23 different letters, each with a different shape and sound.
When you look at a letter like "A", it has an uppercase and lowercase version. The uppercase version is big and the lowercase version is smaller. There are also rules on how to write the letters in a specific way, like "S" always curving to the right and "R" looking like a fancy "P".
People who used the classical Latin alphabet didn't have computers or phones to type things out, so they used special tools called pens and ink to write on paper or parchment. They had to be very careful and take their time so that their letters were neat and easy to read.
Overall, the classical Latin alphabet is a special way that people used to write down words a long time ago. It has its own set of rules and takes practice to use properly.