What are these Alternative CryptoCurrencies that I hear of & See ?

[PhantaSalmon]

Can some people please give me a quick rundown on what these Altcoins are in relation to Bitcoin ?

Are they like Alternative versions of Bitcoin with different Features or Specifications ?

Will they be around for as long as Bitcoin or do they get created & then abandoned ?

[xhomerx10]

Can some people please give me a quick rundown on what these Altcoins are in relation to Bitcoin ?

Are they like Alternative versions of Bitcoin with different Features or Specifications ?

Will they be around for as long as Bitcoin or do they get created & then abandoned ?

 Yes and no some use the same algorithm most use a different one.  Some will make it longer term but most wont.
If you really want a detailed explanation, go here

[The Sceptical Chymist]

They are otherwise known as shitcoins and I think most of them are destined to be worthless--but how long it takes to get to zero, I've no idea.   If you join an exchange like yobit or poloniex you'll see a bewildering array of shitcoins and you won't even know where to begin.   They exist to make their developers rich and that's about it.

[kiklo]

Can some people please give me a quick rundown on what these Altcoins are in relation to Bitcoin ?

Altcoin Announcement Thread
https://bitcointalk.org/index.php?board=159.0

Are they like Alternative versions of Bitcoin with different Features or Specifications ?

Some are PoW Based like BTC,
Others are Proof of Stake based,
Dive into the individual Coins Specifications to understand.
Each is a little different, but those differences can mean a lot.

Will they be around for as long as Bitcoin or do they get created & then abandoned ?

Some are created and abandoned as soon as a few weeks, some has lasted for 2 or 3 years.
Check individual threads for details.

Odds are the successor to BTC is in their somewhere, as to how long any will last will be entirely up to the communities that support each coin.