Definition
A VAR, or value-added reseller, is a company that resells a vendor's products and adds its own services on top. Those services can include design, installation, configuration, integration, training and support. VARs usually earn money from product margin plus the services they sell.
VARs often handle a full project for a customer, pulling together products from several vendors. That makes them trusted advisors on what to buy.
Many VARs have shifted toward recurring services, and some now also run managed services. The line between a VAR and an MSP is often blurry.
In practice
A VAR sells a firewall to a regional bank, designs the network setup, installs it and trains the bank's IT team to manage it.