--- contentType: explanation --- # Processing data with code ## Function A function is a block of code designed to perform a certain task. In n8n, you can write custom JavaScript or Python code snippets to add, remove, and update the data you receive from a node. The [Code](/integrations/builtin/core-nodes/n8n-nodes-base.code/) node gives you access to the incoming data and you can manipulate it. With this node you can create any function you want using JavaScript code.