A placeholder in TensorFlow is basically a variable that you could use to assign a data, even during the runtime. With the help of these placeholders, you could build operations or a graph, without setting up a value or data into these variables.
With TensorFlow, you could add value to these placeholders and get the value from the graph.
If you are interested in learning artificial intelligence with TensorFlow, then I would recommend you take up the artificial intelligence course from Intellipaat.
Also, watch our YouTube video on TensorFlow interview questions which might help you get started.
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