What are IV's worth?

[Xtrm333]

What is the difference in stat points, between 1 IV and 31?

[Walshie]

The number added on to stats at level 100. Say you had a Starmie with 31 IVs in speed, it would have 31 added on to it's speed stat at level 100.

[The Kiwi Dragon]

The number added on to stats at level 100. Say you had a Starmie with 31 IVs in speed, it would have 31 added on to it's speed stat at level 100.

Using your example, in a battle a 31 IV Starmie will outspeed the 1 IV Starmie. In other stats such as HP/Defense/Special Defense it makes the difference between if one of your Pokemon will survive the next attack it takes from the opponent. I.e: A Bulky Shuckle with 31 IVs in HP/Defense/Special Defense will survive a Scald from a Protean Greninja better than that of a Shuckle with 1 IV in each stat.