user84112: I am wondering if you can explain this.
I went here:
https://coinb.in/#newSegWit
Created the SegWit Address below:
3ASaGJ8h2bLn6Jha3hncBzXUKRCLyfv9bk

RedeemScript
037fa484e4b870082298d6acca0702a48714323664c647604e6461d4739feb0d9b

Public key
00147a201aa7e1cfb799dcfc2b447a0238421ae2fa60

Private key (WIF key)
KzVonapu3Cf7DaMpaqkUQ9tpsBQPBH7Yk6tXJdvMwuJSy97GK7dc

Then I opened Electrum  v3.1.3 and Imported WIF Pkey above.
And I got this address instead:
1C8ju39MFSPXNqtYDhsuB3Ek45L46dBr3G

So now there are two addresses,  one SegWit (or I think P2SH) starting with 3... and the legacy address from Electrum starting with 1...
Appreciate an explanation of this.

user60443: There are many types of addresses, see Bitcoin Transaction, each can be created for the same recipient (key pair). For example:

Pay to PubKey Hash (P2PKH) - These start with 1. This is basically just a hash of your public key. If you can prove you own the public key, you can spend it.
Pay to Script Hash (P2SH) - These start with 3. This is a script that you must prove you can satisfy using your private key. There are many types of scripts as well.

They are just different ways of locking Bitcoin for a recipient, but in all of them the recipient must use the private key to satisfy the lock to spend the Bitcoin.

user84976: An overview of the address types, check out: 
https://en.bitcoin.it/wiki/Address
You are looking for P2SH, https://segwitaddress.org/ just scroll down and put in your compressed WIF key at the 'Details' section. 
Further check out https://iancoleman.io/bip39/ 
BIP44, BIP49 and BIP 85 are also implemented in the Coinomi Wallet. 
https://coinomi.freshdesk.com/support/solutions/articles/29000009746-what-are-default-compatibility-and-legacy-addresses-all-about-segwit-

user63872: The same private key can be used to derive a couple of different addresses. For example, there will be a different address generated depending on whether you use a compressed or uncompressed public key in the derivation. 
More relevant to your question, you can use a private key to derive a P2SH-wrapped segwit address (3ASaGJ.. in your example), or just a plain old P2PKH address (1C8ju3.. in your example). Both addresses are spendable using the same private key, since they are both derived from the same private key. 
Note that you should not design a wallet to create segwit addresses using an uncompressed public key (use the compressed key only!), due to potential backwards-compatibility issues in the future.
This image from the bitcoin wiki Address page helps to illustrate this point:


84112: <p>I am wondering if you can explain this.</p>
<p>I went here:
<a href="https://coinb.in/#newSegWit" rel="nofollow noreferrer">https://coinb.in/#newSegWit</a></p>
<p>Created the SegWit Address below:</p>
<pre><code>3ASaGJ8h2bLn6Jha3hncBzXUKRCLyfv9bk
</code></pre>
<p>RedeemScript</p>
<pre><code>037fa484e4b870082298d6acca0702a48714323664c647604e6461d4739feb0d9b
</code></pre>
<p>Public key</p>
<pre><code>00147a201aa7e1cfb799dcfc2b447a0238421ae2fa60
</code></pre>
<p>Private key (WIF key)</p>
<pre><code>KzVonapu3Cf7DaMpaqkUQ9tpsBQPBH7Yk6tXJdvMwuJSy97GK7dc
</code></pre>
<p>Then I opened Electrum  v3.1.3 and Imported WIF Pkey above.</p>
<p>And I got this address instead:</p>
<pre><code>1C8ju39MFSPXNqtYDhsuB3Ek45L46dBr3G
</code></pre>
<p>So now there are two addresses,  one SegWit (or I think P2SH) starting with 3... and the legacy address from Electrum starting with 1...</p>
<p>Appreciate an explanation of this.</p>
 60443: <p>There are many types of addresses, see <a href="https://en.bitcoin.it/wiki/Transaction" rel="nofollow noreferrer">Bitcoin Transaction</a>, each can be created for the same recipient (key pair). For example:</p>

<ul>
<li>Pay to PubKey Hash (P2PKH) - These start with 1. This is basically just a hash of your public key. If you can prove you own the public key, you can spend it.</li>
<li>Pay to Script Hash (P2SH) - These start with 3. This is a script that you must prove you can satisfy using your private key. There are many types of scripts as well.</li>
</ul>

<p>They are just different ways of locking Bitcoin for a recipient, but in all of them the recipient must use the private key to satisfy the lock to spend the Bitcoin.</p>
 84976: <p>An overview of the address types, check out: 
<a href="https://en.bitcoin.it/wiki/Address" rel="nofollow noreferrer">https://en.bitcoin.it/wiki/Address</a></p>

<p>You are looking for P2SH, <a href="https://segwitaddress.org/" rel="nofollow noreferrer">https://segwitaddress.org/</a> just scroll down and put in your compressed WIF key at the 'Details' section. </p>

<p>Further check out <a href="https://iancoleman.io/bip39/" rel="nofollow noreferrer">https://iancoleman.io/bip39/</a> </p>

<p>BIP44, BIP49 and BIP 85 are also implemented in the Coinomi Wallet. </p>

<p><a href="https://coinomi.freshdesk.com/support/solutions/articles/29000009746-what-are-default-compatibility-and-legacy-addresses-all-about-segwit-" rel="nofollow noreferrer">https://coinomi.freshdesk.com/support/solutions/articles/29000009746-what-are-default-compatibility-and-legacy-addresses-all-about-segwit-</a></p>
 63872: <p>The same private key can be used to derive a couple of different addresses. For example, there will be a different address generated depending on whether you use a compressed or uncompressed public key in the derivation. </p>

<p>More relevant to your question, you can use a private key to derive a P2SH-wrapped segwit address (<code>3ASaGJ..</code> in your example), or just a plain old P2PKH address (<code>1C8ju3..</code> in your example). Both addresses are spendable using the same private key, since they are both derived from the same private key. </p>

<p>Note that you should <strong>not</strong> design a wallet to create segwit addresses using an uncompressed public key (use the compressed key only!), due to potential backwards-compatibility issues in the future.</p>

<p>This image from the <a href="https://en.bitcoin.it/wiki/Address" rel="noreferrer">bitcoin wiki Address page</a> helps to illustrate this point:</p>

<p><a href="https://i.stack.imgur.com/YgJUD.jpg" rel="noreferrer"><img src="https://i.stack.imgur.com/YgJUD.jpg" alt="Bitcoin Address Derivation Map"></a></p>
