They are numbers that terminate.
The set of your friends is finite. The set of counting numbers (part of which you will use to count your friends) is infinite.
A finite set is a set that has numbers you can count. Its not like infinite with no end it has an end.
Some finite numbers in a set: the number of digits on your hand, the number of seats on a bus, and the number of people on earth. Some infinite numbers in a set: the number of positive integers and the number of digits in pi.
They are sets with a finite number of elements. For example the days of the week, or the 12 months of the year. Modular arithmetic is based on finite sets.
YES
Closed sets and open sets, or finite and infinite sets.
This is called a discrete set (all points isolated) or a finite set. Finite sets are always discrete.
Closed sets and open sets, or finite and infinite sets.
Closed sets and open sets, or finite and infinite sets.
Closed sets and open sets, or finite and infinite sets.
There are finite sets, countably infinite sets and uncountably infinite sets.