diff --git a/contrib/debian/changelog b/contrib/debian/changelog
index 7ce3babc1..bd7ab3524 100644
--- a/contrib/debian/changelog
+++ b/contrib/debian/changelog
@@ -149,7 +149,7 @@ bitcoin (0.5.3-natty0) natty; urgency=low
 bitcoin (0.5.2-natty1) natty; urgency=low
 
   * Remove mentions on anonymity in package descriptions and manpage.
-    These should never have been there, bitcoin isnt anonymous without
+    These should never have been there, bitcoin isn't anonymous without
     a ton of work that virtually no users will ever be willing and
     capable of doing
 
@@ -190,7 +190,7 @@ bitcoin (0.5.0~rc1-natty1) natty; urgency=low
 
   * Add test_bitcoin to build test
   * Fix clean
-  * Remove uneccessary build-dependancies
+  * Remove unnecessary build-dependancies
 
  -- Matt Corallo <matt@bluematt.me>  Wed, 26 Oct 2011 14:37:18 -0400
 
@@ -350,7 +350,7 @@ bitcoin (0.3.20.01~dfsg-1) unstable; urgency=low
 
 bitcoin (0.3.19~dfsg-6) unstable; urgency=low
 
-  * Fix override agressive optimizations.
+  * Fix override aggressive optimizations.
   * Fix tighten build-dependencies to really fit backporting to Lenny:
     + Add fallback build-dependency on libdb4.6++-dev.
     + Tighten unversioned Boost build-dependencies to recent versions,
diff --git a/depends/config.guess b/depends/config.guess
index f7eb141e7..f357ec6c8 100755
--- a/depends/config.guess
+++ b/depends/config.guess
@@ -1117,7 +1117,7 @@ EOF
 	# uname -m prints for DJGPP always 'pc', but it prints nothing about
 	# the processor, so we play safe by assuming i586.
 	# Note: whatever this is, it MUST be the same as what config.sub
-	# prints for the "djgpp" host, or else GDB configury will decide that
+	# prints for the "djgpp" host, or else GDB configure will decide that
 	# this is a cross-build.
 	echo i586-pc-msdosdjgpp
 	exit ;;
diff --git a/qa/rpc-tests/rest.py b/qa/rpc-tests/rest.py
index b0cde7268..eca655a59 100755
--- a/qa/rpc-tests/rest.py
+++ b/qa/rpc-tests/rest.py
@@ -200,7 +200,7 @@ class RESTTest (BitcoinTestFramework):
         response = http_get_call(url.hostname, url.port, '/rest/getutxos'+json_request+self.FORMAT_SEPARATOR+'json', '', True)
         assert_equal(response.status, 200) #must be a 500 because we exceeding the limits
 
-        self.nodes[0].generate(1) #generate block to not affect upcomming tests
+        self.nodes[0].generate(1) #generate block to not affect upcoming tests
         self.sync_all()
 
         ################
diff --git a/qa/rpc-tests/test_framework/comptool.py b/qa/rpc-tests/test_framework/comptool.py
index 7fb31d4a0..f4808df08 100755
--- a/qa/rpc-tests/test_framework/comptool.py
+++ b/qa/rpc-tests/test_framework/comptool.py
@@ -116,7 +116,7 @@ class TestNode(NodeConnCB):
 #    is reached) and then sent out in one inv message.  Then the final block
 #    will be synced across all connections, and the outcome of the final 
 #    block will be tested.
-# sync_every_tx: analagous to behavior for sync_every_block, except if outcome
+# sync_every_tx: analogous to behavior for sync_every_block, except if outcome
 #    on the final tx is None, then contents of entire mempool are compared
 #    across all connections.  (If outcome of final tx is specified as true
 #    or false, then only the last tx is tested against outcome.)
diff --git a/src/addrman.h b/src/addrman.h
index 2623d8980..384b6cfdb 100644
--- a/src/addrman.h
+++ b/src/addrman.h
@@ -265,7 +265,7 @@ public:
      * Notice that vvTried, mapAddr and vVector are never encoded explicitly;
      * they are instead reconstructed from the other information.
      *
-     * vvNew is serialized, but only used if ADDRMAN_UNKOWN_BUCKET_COUNT didn't change,
+     * vvNew is serialized, but only used if ADDRMAN_UNKNOWN_BUCKET_COUNT didn't change,
      * otherwise it is reconstructed as well.
      *
      * This format is more complex, but significantly smaller (at most 1.5 MiB), and supports
diff --git a/src/main.cpp b/src/main.cpp
index 79cc60685..34e163ff6 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -1471,7 +1471,7 @@ bool AbortNode(const std::string& strMessage, const std::string& userMessage="")
     strMiscWarning = strMessage;
     LogPrintf("*** %s\n", strMessage);
     uiInterface.ThreadSafeMessageBox(
-        userMessage.empty() ? _("Error: A fatal internal error occured, see debug.log for details") : userMessage,
+        userMessage.empty() ? _("Error: A fatal internal error occurred, see debug.log for details") : userMessage,
         "", CClientUIInterface::MSG_ERROR);
     StartShutdown();
     return false;
diff --git a/src/merkleblock.cpp b/src/merkleblock.cpp
index 4d90fd8cd..f8e877df2 100644
--- a/src/merkleblock.cpp
+++ b/src/merkleblock.cpp
@@ -168,7 +168,7 @@ uint256 CPartialMerkleTree::ExtractMatches(std::vector<uint256> &vMatch) {
     // traverse the partial tree
     unsigned int nBitsUsed = 0, nHashUsed = 0;
     uint256 hashMerkleRoot = TraverseAndExtract(nHeight, 0, nBitsUsed, nHashUsed, vMatch);
-    // verify that no problems occured during the tree traversal
+    // verify that no problems occurred during the tree traversal
     if (fBad)
         return uint256();
     // verify that all bits were consumed (except for the padding caused by serializing it as a byte sequence)
diff --git a/src/net.cpp b/src/net.cpp
index e4ead3c92..fb5726a2b 100644
--- a/src/net.cpp
+++ b/src/net.cpp
@@ -2319,7 +2319,7 @@ void DumpBanlist()
 {
     int64_t nStart = GetTimeMillis();
 
-    CNode::SweepBanned(); //clean unused entires (if bantime has expired)
+    CNode::SweepBanned(); //clean unused entries (if bantime has expired)
 
     CBanDB bandb;
     banmap_t banmap;
diff --git a/src/net.h b/src/net.h
index efa2e29bb..954cdd49d 100644
--- a/src/net.h
+++ b/src/net.h
@@ -695,7 +695,7 @@ public:
     static bool BannedSetIsDirty();
     //!set the "dirty" flag for the banlist
     static void SetBannedSetDirty(bool dirty=true);
-    //!clean unused entires (if bantime has expired)
+    //!clean unused entries (if bantime has expired)
     static void SweepBanned();
 
     void copyStats(CNodeStats &stats);
diff --git a/src/netbase.cpp b/src/netbase.cpp
index b7e2e5791..dec00e1ee 100644
--- a/src/netbase.cpp
+++ b/src/netbase.cpp
@@ -349,7 +349,7 @@ static bool Socks5(const std::string& strDest, int port, const ProxyCredentials
         }
         if (pchRetA[0] != 0x01 || pchRetA[1] != 0x00) {
             CloseSocket(hSocket);
-            return error("Proxy authentication unsuccesful");
+            return error("Proxy authentication unsuccessful");
         }
     } else if (pchRet1[1] == 0x00) {
         // Perform no authentication
diff --git a/src/policy/fees.cpp b/src/policy/fees.cpp
index cdee541d2..ffe31d194 100644
--- a/src/policy/fees.cpp
+++ b/src/policy/fees.cpp
@@ -261,7 +261,7 @@ void TxConfirmStats::removeTx(unsigned int entryHeight, unsigned int nBestSeenHe
         blocksAgo = 0;
     if (blocksAgo < 0) {
         LogPrint("estimatefee", "Blockpolicy error, blocks ago is negative for mempool tx\n");
-        return;  //This can't happen becasue we call this with our best seen height, no entries can have higher
+        return;  //This can't happen because we call this with our best seen height, no entries can have higher
     }
 
     if (blocksAgo >= (int)unconfTxs.size()) {
diff --git a/src/policy/fees.h b/src/policy/fees.h
index ce4d78256..15577d128 100644
--- a/src/policy/fees.h
+++ b/src/policy/fees.h
@@ -118,7 +118,7 @@ public:
     /**
      * Initialize the data structures.  This is called by BlockPolicyEstimator's
      * constructor with default values.
-     * @param defaultBuckets contains the upper limits for the bucket boundries
+     * @param defaultBuckets contains the upper limits for the bucket boundaries
      * @param maxConfirms max number of confirms to track
      * @param decay how much to decay the historical moving average per block
      * @param dataTypeString for logging purposes
diff --git a/src/qt/paymentserver.cpp b/src/qt/paymentserver.cpp
index 0827d9912..5cc4d00db 100644
--- a/src/qt/paymentserver.cpp
+++ b/src/qt/paymentserver.cpp
@@ -762,7 +762,7 @@ void PaymentServer::setOptionsModel(OptionsModel *optionsModel)
 
 void PaymentServer::handlePaymentACK(const QString& paymentACKMsg)
 {
-    // currently we don't futher process or store the paymentACK message
+    // currently we don't further process or store the paymentACK message
     Q_EMIT message(tr("Payment acknowledged"), paymentACKMsg, CClientUIInterface::ICON_INFORMATION | CClientUIInterface::MODAL);
 }
 
diff --git a/src/qt/rpcconsole.cpp b/src/qt/rpcconsole.cpp
index 3231b392f..4453ceb56 100644
--- a/src/qt/rpcconsole.cpp
+++ b/src/qt/rpcconsole.cpp
@@ -570,7 +570,7 @@ void RPCConsole::peerLayoutChanged()
 
     if (detailNodeRow < 0)
     {
-        // detail node dissapeared from table (node disconnected)
+        // detail node disappeared from table (node disconnected)
         fUnselect = true;
     }
     else
diff --git a/src/qt/splashscreen.cpp b/src/qt/splashscreen.cpp
index 8430e017c..c15b64c32 100644
--- a/src/qt/splashscreen.cpp
+++ b/src/qt/splashscreen.cpp
@@ -57,7 +57,7 @@ SplashScreen::SplashScreen(Qt::WindowFlags f, const NetworkStyle *networkStyle)
     QPainter pixPaint(&pixmap);
     pixPaint.setPen(QColor(100,100,100));
 
-    // draw a slighly radial gradient
+    // draw a slightly radial gradient
     QRadialGradient gradient(QPoint(0,0), splashSize.width()/devicePixelRatio);
     gradient.setColorAt(0, Qt::white);
     gradient.setColorAt(1, QColor(247,247,247));
diff --git a/src/rpcserver.cpp b/src/rpcserver.cpp
index 68091010f..56993f32f 100644
--- a/src/rpcserver.cpp
+++ b/src/rpcserver.cpp
@@ -606,7 +606,7 @@ void StartRPCThreads()
         LogPrintf("No rpcpassword set - using random cookie authentication\n");
         if (!GenerateAuthCookie(&strRPCUserColonPass)) {
             uiInterface.ThreadSafeMessageBox(
-                _("Error: A fatal internal error occured, see debug.log for details"), // Same message as AbortNode
+                _("Error: A fatal internal error occurred, see debug.log for details"), // Same message as AbortNode
                 "", CClientUIInterface::MSG_ERROR);
             StartShutdown();
             return;
@@ -670,7 +670,7 @@ void StartRPCThreads()
         vEndpoints.push_back(ip::tcp::endpoint(boost::asio::ip::address_v6::any(), defaultPort));
         vEndpoints.push_back(ip::tcp::endpoint(boost::asio::ip::address_v4::any(), defaultPort));
         // Prefer making the socket dual IPv6/IPv4 instead of binding
-        // to both addresses seperately.
+        // to both addresses separately.
         bBindAny = true;
     }
 
diff --git a/src/sync.h b/src/sync.h
index 705647e4a..68a944308 100644
--- a/src/sync.h
+++ b/src/sync.h
@@ -16,7 +16,7 @@
 
 ////////////////////////////////////////////////
 //                                            //
-// THE SIMPLE DEFINITON, EXCLUDING DEBUG CODE //
+// THE SIMPLE DEFINITION, EXCLUDING DEBUG CODE //
 //                                            //
 ////////////////////////////////////////////////
 
diff --git a/src/test/data/tx_invalid.json b/src/test/data/tx_invalid.json
index 20bdbd08a..6c3cac71c 100644
--- a/src/test/data/tx_invalid.json
+++ b/src/test/data/tx_invalid.json
@@ -128,7 +128,7 @@
 [[["0000000000000000000000000000000000000000000000000000000000000100", 0, "499999999 NOP2 1"]],
 "0100000001000100000000000000000000000000000000000000000000000000000000000000000000000000000001000000000000000000fe64cd1d", "P2SH,CHECKLOCKTIMEVERIFY"],
 
-["By-time locks, with argument just beyond tx nLockTime (but within numerical boundries)"],
+["By-time locks, with argument just beyond tx nLockTime (but within numerical boundaries)"],
 [[["0000000000000000000000000000000000000000000000000000000000000100", 0, "500000001 NOP2 1"]],
 "01000000010001000000000000000000000000000000000000000000000000000000000000000000000000000000010000000000000000000065cd1d", "P2SH,CHECKLOCKTIMEVERIFY"],
 [[["0000000000000000000000000000000000000000000000000000000000000100", 0, "4294967295 NOP2 1"]],
diff --git a/src/test/data/tx_valid.json b/src/test/data/tx_valid.json
index 24fff575c..9744a3c84 100644
--- a/src/test/data/tx_valid.json
+++ b/src/test/data/tx_valid.json
@@ -197,7 +197,7 @@
 [[["0000000000000000000000000000000000000000000000000000000000000100", 0, "0 NOP2 1"]],
 "0100000001000100000000000000000000000000000000000000000000000000000000000000000000000000000001000000000000000000ff64cd1d", "P2SH,CHECKLOCKTIMEVERIFY"],
 
-["By-time locks, with argument just beyond tx nLockTime (but within numerical boundries)"],
+["By-time locks, with argument just beyond tx nLockTime (but within numerical boundaries)"],
 [[["0000000000000000000000000000000000000000000000000000000000000100", 0, "500000000 NOP2 1"]],
 "01000000010001000000000000000000000000000000000000000000000000000000000000000000000000000000010000000000000000000065cd1d", "P2SH,CHECKLOCKTIMEVERIFY"],
 [[["0000000000000000000000000000000000000000000000000000000000000100", 0, "4294967295 NOP2 1"]],
diff --git a/src/wallet/rpcwallet.cpp b/src/wallet/rpcwallet.cpp
index 198b5baf6..ce547f575 100644
--- a/src/wallet/rpcwallet.cpp
+++ b/src/wallet/rpcwallet.cpp
@@ -797,7 +797,7 @@ UniValue movecmd(const UniValue& params, bool fHelp)
             "4. minconf           (numeric, optional, default=1) Only use funds with at least this many confirmations.\n"
             "5. \"comment\"       (string, optional) An optional comment, stored in the wallet only.\n"
             "\nResult:\n"
-            "true|false           (boolean) true if successfull.\n"
+            "true|false           (boolean) true if successful.\n"
             "\nExamples:\n"
             "\nMove 0.01 " + CURRENCY_UNIT + " from the default account to the account named tabby\n"
             + HelpExampleCli("move", "\"\" \"tabby\" 0.01") +