Update Glossary (#310)

Adding smart contract terms to Glossary

docs/glossary.mdx

@@ -97,6 +97,12 @@ The type of encoding used operations and data running on stellar-core.
 
 Flags control access to an asset on the account level. Learn more about flags in our [Controlling Access to an Asset section](./issuing-assets/control-asset-access#controlling-access-to-an-asset-with-flags).
 
+### Fuzzing
+
+An automated test that rapidly stuffs massive amounts of randomized, malformed data into a system to reveal adverse or unexpected results that indicate vulnerabilities.
+
+Read more in the [Fuzz Testing Tutorial](https://soroban.stellar.org/docs/tutorials/fuzzing).
+
 ### GitHub
 
 An online repository for documents that can be accessed and shared among multiple users; host for the Stellar platform’s source code, documentation, and other open-source repos.
@@ -245,6 +251,10 @@ Refers to the master key or to any other signing keys added later. A signer is d
 
 See our [Signature and Multisignature Encyclopedia Entry](./encyclopedia/signatures-multisig) for more information.
 
+### Smart contract
+
+Self-executing contracts with the terms of the agreement directly written into code, automatically enforceable without the need for intermediaries.
+
 ### Source account
 
 The account that originates a transaction. This account also provides the fee and sequence number for the transaction.
@@ -323,6 +333,16 @@ An explicit opt-in for an account to hold a particular asset that tracks liabili
 
 Learn more in our [Accounts section](./fundamentals-and-concepts/stellar-data-structures/accounts#trustlines).
 
+### TTL (Time To Live)
+
+A smart contract's TTL is how many ledgers remain until the data entry is no longer live.
+
+Read more in the [State Archival section](https://soroban.stellar.org/docs/soroban-internals/state-archival#ttl).
+
+### Type
+
+The classification of data that dictates the kind of data that can be stored and how it can be manipulated within a smart contract.
+
 ### UNIX timestamp
 
 An integer representing a given date and time, as used on UNIX and Linux computers.