Asynchronous vs. Synchronous: What’s The Difference?

Synchronous means happening at the same time. Asynchronous is the opposite — not happening at the same time. Synchronous learning involves students interacting with a teacher in real time, while asynchronous learning involves students working outside of a classroom setting and at their own pace.

Synchronous vs. asynchronous learning

Traditional schooling is largely synchronous, with students engaging in synchronous learning in classrooms in brick-and-mortar buildings. Virtual classrooms — such as those conducted via two-way video technology, often recreate this synchronous experience with a teacher instructing a “room” of students in real time, with the ability for the teacher to ask questions and for the students to respond.

In an asynchronous course, a student does not need to meet in real time with a live class or teacher. Instead of the constraints of a traditional classroom, students participating in asynchronous learning can move through assignments at their own speed and are often aided by online discussion boards and emails.

Many virtual learning environments incorporate a mix of synchronous and asynchronous learning, in which students spend some time in a live virtual classroom and then go off to complete assignments on their own.

Where do the words synchronous and asynchronous come from?

Synchronous uses the Greek syn-, meaning “together.” The middle part of the word comes from the Greek chron(os), meaning “time.” The ending -ous is used to form adjectives. Based on its word parts, synchronous basically means “happening at the same time.” Asynchronous uses the prefix a-, meaning “not,” making it the opposite: “not happening at the same time.”

How to use synchronous vs. asynchronous

Things that happen together and at the same time are synchronous. Asynchronous is the opposite — it describes things that happen at staggered times or not together in real time.

In the context of education, synchronous learning involves learning together in real time — a direct back-and-forth between teacher and students. Asynchronous learning involves students working on their own and at their own pace outside of a traditional classroom or video classroom setting.

In the context of communication, talking to someone in person, over the phone, or over video chat are all considered synchronous because they happen together and at the same time. Email, on the other hand, is an asynchronous form of communication.