To allow, well come in.

The most nonsensical way to greet someone into your place of business

1. Welcome is the way of greeting someone of their presence in your location.

Slang used in the South to describe a bad situation or place. Welcome...to hell.

People use Welcome because it is shorter then

“You’re Welcome”

When someone is truly thankful to you, this describes you saying "You're Welcome" with emphasis.

get down in a crouch position then put your arms cross ways and just dance with your legs flapping and your tounge hanging out and make stupid noises.