Strong two-bids form one of the cornerstones of the ACOL system. Except for an opening bid of 2♣ (or 2NT for that matter) an opening two-bid shows a hand of "power and quality" based on a very good suit (or on two very good suits).
One yardstick (not the only one) is that a two-bid should contain at least eight playing tricks. In other words, a two-bidder should expect to make eight tricks out of his own hand, even facing garbage.
An opening ACOL two-bid is FORCING. In other words, partner may not Pass a two-bid no matter how poor his hand is.
ACOL two-bids are not based on the point-count. Bear that in mind - it is an important point.