I was analysing my website traffic and i saw this....

I was analysing my friend's website traffic to learn about all these analytics metrices and i saw this UNIQUE PAGE VIEWS and ENTRANCE and i could not diffrentiate these both terms. can any one tell me the diffrence ?

Entrances show how many times the page was visited first in the session.

Unique pageviews means number of views by the same user during the same session. I think we could consider this as a combination of pageviews where they all count as one.