While the other answers here provide good descriptions for the NAT and Bridged modes, their explanations for Host-only mode are not quite accurate.

From VMware's documentation, under Configuring Network Connections > Understanding Common Networking Configurations:

Host-only networking creates a network that is completely contained within the host computer. Host-only networking provides a network connection between the virtual machine and the host system by using a virtual network adapter that is visible on the host operating system.

(Emphasis mine.)

Note that it does not say that the VM will be accessible only by the host. The network is self-contained, not the connection. This is a subtle but important difference.

You should be aware that the Host-only, NAT, and Bridged modes are aliases to specific virtual networking switches ("VMnets") that are preconfigured for the different behaviors. As with a normal network switch, all machines connected to the same switch are visible to each other.

This means that all VMs connected to a host-only network will be visible to the host and to each other. If you want a VM that is visible only to the host, you will need to assign it a dedicated VMnet and avoid assigning any other VMs to that VMnet.

While the other answers here provide good descriptions for the NAT and Bridged modes, their explanations for Host-only mode are not quite accurate.

From VMware's documentation, under Configuring Network Connections > Understanding Common Networking Configurations:

Host-only networking creates a network that is completely contained within the host computer. Host-only networking provides a network connection between the virtual machine and the host system by using a virtual network adapter that is visible on the host operating system.

(Emphasis mine.)

Note that it does not say that the VM will be accessible only by the host. The network is self-contained, not the connection. This is a subtle but important difference.

Additionally, as pointed out by user5389726598465, under Creating Virtual Machines > Preparing to Create a New Virtual Machine > Selecting the Network Connection Type for a Virtual Machine:

With host-only networking, the virtual machine can communicate only with the host system and other virtual machines in the host-only network. Select host-only networking to set up an isolated virtual network.

You should be aware that the Host-only, NAT, and Bridged modes are aliases to specific virtual networking switches ("VMnets") that are preconfigured for the different behaviors. As with a normal network switch, all machines connected to the same switch are visible to each other.

This means that all VMs connected to a host-only network will be visible to the host and to each other. If you want a VM that is visible only to the host, you will need to assign it a dedicated VMnet and avoid assigning any other VMs to that VMnet.

While the other answers here provide good descriptions for the NAT and Bridged modes, their explanations for Host-only mode are not quite accurate.

From VMware's documentation (emphasis mine):

Host-only networking creates a network that is completely contained within the host computer. Host-only networking provides a network connection between the virtual machine and the host system by using a virtual network adapter that is visible on the host operating system.

Note that it does not say that the VM will be accessible only by the host. The network is self-contained, not the connection. This is a subtle but important difference.

You should be aware that the Host-only, NAT, and Bridged modes are aliases to specific virtual networking switches ("VMnets") that are preconfigured for the different behaviors. As with a normal network switch, all machines connected to the same switch are visible to each other.

This means that all VMs connected to a host-only network will be visible to the host and to each other. If you want a VM that is visible only to the host, you will need to assign it a dedicated VMnet and avoid assigning any other VMs to that VMnet.

While the other answers here provide good descriptions for the NAT and Bridged modes, their explanations for Host-only mode are not quite accurate.

From VMware's documentation, under Configuring Network Connections > Understanding Common Networking Configurations:

Host-only networking creates a network that is completely contained within the host computer. Host-only networking provides a network connection between the virtual machine and the host system by using a virtual network adapter that is visible on the host operating system.

(Emphasis mine.)

Note that it does not say that the VM will be accessible only by the host. The network is self-contained, not the connection. This is a subtle but important difference.

You should be aware that the Host-only, NAT, and Bridged modes are aliases to specific virtual networking switches ("VMnets") that are preconfigured for the different behaviors. As with a normal network switch, all machines connected to the same switch are visible to each other.

This means that all VMs connected to a host-only network will be visible to the host and to each other. If you want a VM that is visible only to the host, you will need to assign it a dedicated VMnet and avoid assigning any other VMs to that VMnet.