diff --git a/Module.h b/Module.h
index cd8ae1fb5..910dec705 100644
--- a/Module.h
+++ b/Module.h
@@ -102,7 +102,7 @@ class Module : public PScope, public LineInfo {
 	    bool signed_flag;
 	      // Value expression
 	    PExpr*expr;
-	      // If there are range constrants, list them here
+	      // If there are range constraints, list them here
 	    range_t*range;
       };
       map<perm_string,param_expr_t>parameters;
diff --git a/driver/main.c b/driver/main.c
index 4fb995f0e..38c4d1bba 100644
--- a/driver/main.c
+++ b/driver/main.c
@@ -506,7 +506,7 @@ int process_generation(const char*name)
 		            "    2005 -- IEEE1364-2005\n"
 		            "Other generation flags:\n"
 		            "    specify | no-specify\n"
-		            "    verilog-ams | no-verinlog-ams\n"
+		            "    verilog-ams | no-verilog-ams\n"
 		            "    std-include | no-std-include\n"
 		            "    xtypes | no-xtypes\n"
 		            "    icarus-misc | no-icarus-misc\n"
diff --git a/elaborate.cc b/elaborate.cc
index eb93811bd..26740120e 100644
--- a/elaborate.cc
+++ b/elaborate.cc
@@ -386,7 +386,7 @@ void PGBuiltin::elaborate(Design*des, NetScope*scope) const
 	    high = msb.as_long();
 
 	    if (debug_elaborate) {
-		  cerr << get_fileline() << ": debug: PGBuiltin: Make arrray "
+		  cerr << get_fileline() << ": debug: PGBuiltin: Make array "
 		       << "[" << high << ":" << low << "]"
 		       << " of " << count << " gates for " << name << endl;
 	    }
@@ -1189,8 +1189,8 @@ void PGModule::elaborate_mod_(Design*des, Module*rmod, NetScope*scope) const
 		       identifier elaborates to the same NetNet in
 		       both cases so the extra elaboration has no
 		       effect. But if the expression passed to the
-		       inout port is a part select, aspecial part
-		       select must be created that can paqss data in
+		       inout port is a part select, a special part
+		       select must be created that can pass data in
 		       both directions.
 
 		       Use the elaborate_bi_net method to handle all
@@ -3055,7 +3055,7 @@ NetProc* PForStatement::elaborate(Design*des, NetScope*scope) const
       sig = des->find_signal(scope, id2->path());
       if (sig == 0) {
 	    cerr << get_fileline() << ": error: Unable to find variable "
-		 << id2->path() << " in for-loop increment expressin." << endl;
+		 << id2->path() << " in for-loop increment expression." << endl;
 	    des->errors += 1;
 	    return body;
       }
diff --git a/emit.cc b/emit.cc
index 079a41c84..606d13beb 100644
--- a/emit.cc
+++ b/emit.cc
@@ -362,7 +362,7 @@ void NetScope::emit_scope(struct target_t*tgt) const
 	      /* Run the signals again, but this time to connect the
 	         delay paths. This is done as a second pass because
 	         the paths reference other signals that may be later
-	         in the list. We can do it here becase delay paths are
+	         in the list. We can do it here because delay paths are
 	         always connected within the scope. */
 	    cur = signals_->sig_next_;
 	    do {
diff --git a/expr_synth.cc b/expr_synth.cc
index 3f079fc5c..df291f6d1 100644
--- a/expr_synth.cc
+++ b/expr_synth.cc
@@ -459,7 +459,7 @@ NetNet* NetEBDiv::synthesize(Design*des)
 
 	  default: {
 		cerr << get_fileline() << ": internal error: "
-		     << "NetEBDiv has unexpeced op() code: "
+		     << "NetEBDiv has unexpected op() code: "
 		     << op() << endl;
 		des->errors += 1;
 
diff --git a/ivlpp/lexor.lex b/ivlpp/lexor.lex
index 098ef38f7..c4ac34fc3 100644
--- a/ivlpp/lexor.lex
+++ b/ivlpp/lexor.lex
@@ -941,7 +941,7 @@ static void do_define()
     }
 
     /* Detect the continuation sequence. If I find it, remove it
-     * and the white space that preceeds it, then replace all that
+     * and the white space that precedes it, then replace all that
      * with a single newline.
      */
     if ((cp > yytext) && (cp[-1] == '\\'))
diff --git a/lexor.lex b/lexor.lex
index d0dfa7980..936f5ce0f 100644
--- a/lexor.lex
+++ b/lexor.lex
@@ -843,7 +843,7 @@ static verinum*make_unsized_dec(const char*ptr)
       if (ptr[0] == '\'') {
 	      /* The number has decorations of the form 'sd<digits>,
 		 possibly with space between the d and the <digits>.
-		 Also, the 's' is optional, and markes the number as
+		 Also, the 's' is optional, and marks the number as
 		 signed. */
 	    ptr += 1;
 
diff --git a/net_scope.cc b/net_scope.cc
index c8a986fb2..2b8baf0cb 100644
--- a/net_scope.cc
+++ b/net_scope.cc
@@ -166,7 +166,7 @@ bool NetScope::replace_parameter(perm_string key, NetExpr*expr)
 
 /*
  * This is not really complete (msb, lsb, sign). It is currently only
- * used to add a genver to the local parameter list.
+ * used to add a genvar to the local parameter list.
  */
 NetExpr* NetScope::set_localparam(perm_string key, NetExpr*expr,
 				  const LineInfo&file_line)
@@ -275,7 +275,7 @@ const NetFuncDef* NetScope::func_def() const
 void NetScope::set_module_name(perm_string n)
 {
       assert(type_ == MODULE);
-      module_name_ = n; /* NOTE: n mus have been permallocated. */
+      module_name_ = n; /* NOTE: n must have been permallocated. */
 }
 
 perm_string NetScope::module_name() const
diff --git a/net_tran.cc b/net_tran.cc
index 2975970d1..b28a28753 100644
--- a/net_tran.cc
+++ b/net_tran.cc
@@ -128,7 +128,7 @@ void join_island(NetObj*obj)
 		  if (branch->island == 0) {
 			if (debug_elaborate)
 			      cerr << obj->get_fileline() << ": debug: "
-				   << "Join brach to existing island." << endl;
+				   << "Join branch to existing island." << endl;
 			branch->island = tmp_branch->island;
 
 		  } else if (branch->island != tmp_branch->island) {
@@ -139,7 +139,7 @@ void join_island(NetObj*obj)
 	    }
       }
 
-	// If after all that we did not find an idland to join, then
+	// If after all that we did not find an island to join, then
 	// start the island not and join it.
       if (branch->island == 0) {
 	    branch->island = new ivl_island_s;
diff --git a/netlist.h b/netlist.h
index 50b42b879..e23fcb3fd 100644
--- a/netlist.h
+++ b/netlist.h
@@ -827,7 +827,7 @@ class NetScope : public Attrib {
 
 /*
  * This class implements the LPM_ABS component. The node has a single
- * input, a signe expression, that it converts to the absolute
+ * input, a signed expression, that it converts to the absolute
  * value. The gate is simple: pin(0) is the output and pin(1) is the input.
  */
 class NetAbs  : public NetNode {
diff --git a/parse.y b/parse.y
index 75886dffc..de839b334 100644
--- a/parse.y
+++ b/parse.y
@@ -432,7 +432,7 @@ block_item_decl
 
   /* Integer declarations are simpler in that they do not have all the
      trappings of a general variable declaration. All of that is
-     implicit in the "integer" of the declaratin. */
+     implicit in the "integer" of the declaration. */
 
 	| attribute_list_opt K_integer register_variable_list ';'
 		{ pform_set_reg_integer($3);
@@ -445,7 +445,7 @@ block_item_decl
 
   /* real declarations are fairly simple as there is no range of
      signed flag in the declaration. Create the real as a NetNet::REG
-     with real value. Note that real and realtime are interchangable
+     with real value. Note that real and realtime are interchangeable
      in this context. */
 
   | attribute_list_opt K_real real_variable_list ';'
diff --git a/scripts/MAKE_SNAPSHOT.sh b/scripts/MAKE_SNAPSHOT.sh
index b06437b7f..aacf28ac6 100644
--- a/scripts/MAKE_SNAPSHOT.sh
+++ b/scripts/MAKE_SNAPSHOT.sh
@@ -7,7 +7,7 @@
 #    sh scripts/MAKE_SNAPSHOT.sh 20080428 ~/tmp
 #
 # The above assumes that there is a tag "s20080428" at the point
-# to be snaphot. (The tag has the "s", but the argument to this
+# to be snapshot. (The tag has the "s", but the argument to this
 # script does not have the "s"). This script extracts based on the
 # tag, uses the temporary directory to stage intermediate results,
 # and finally creates a file called verilog-20080428.tar.gz that
diff --git a/synth2.cc b/synth2.cc
index 0217554f1..812dceb03 100644
--- a/synth2.cc
+++ b/synth2.cc
@@ -598,7 +598,7 @@ bool NetCondit::synth_sync(Design*des, NetScope*scope, NetFF*ff,
       delete expr_input;
 
 	/* Detect the case that this is a *synchronous* set/reset. It
-	   is not asyncronous because we know the condition is not
+	   is not asynchronous because we know the condition is not
 	   included in the sensitivity list, but if the if_ case is
 	   constant (has no inputs) then we can model this as a
 	   synchronous set/reset.
diff --git a/tgt-vvp/vvp_priv.h b/tgt-vvp/vvp_priv.h
index 4a5a29d31..e6ba5c32b 100644
--- a/tgt-vvp/vvp_priv.h
+++ b/tgt-vvp/vvp_priv.h
@@ -94,7 +94,7 @@ extern void pad_expr_in_place(ivl_expr_t exp, struct vector_info res, unsigned s
  * draw_modpath arranges for a .modpath record to be written out.
  *
  * cleanup_modpath() cleans up any pending .modpath records that may
- * have been scheduled by draw_modpath() but not yet writte.
+ * have been scheduled by draw_modpath() but not yet written.
  *
  * Note: draw_modpath drive_label must be malloc'ed by the
  * caller. This function will free the string sometime in the future.
diff --git a/verinum.cc b/verinum.cc
index 0cd787a61..87f28de04 100644
--- a/verinum.cc
+++ b/verinum.cc
@@ -508,7 +508,7 @@ verinum trim_vnum(const verinum&that)
 
 	      /* Now top is the index of the highest non-zero bit. If
 		 that turns out to the highest bit in the vector, then
-		 tere is no trimming possible. */
+		 there is no trimming possible. */
 	    if (top+1 == that.len())
 		  return that;
 
diff --git a/vpi/sdf_lexor.lex b/vpi/sdf_lexor.lex
index c14b89cca..0a92c5eb6 100644
--- a/vpi/sdf_lexor.lex
+++ b/vpi/sdf_lexor.lex
@@ -139,7 +139,7 @@ static int lookup_keyword(const char*text)
 }
 
 /*
- * Create a string witout the leading and trailing quotes.
+ * Create a string without the leading and trailing quotes.
  */
 static void process_quoted_string(void)
 {
diff --git a/vpi/sys_display.c b/vpi/sys_display.c
index c03da8606..0cd571cc9 100644
--- a/vpi/sys_display.c
+++ b/vpi/sys_display.c
@@ -267,7 +267,7 @@ static void format_time(unsigned mcd, int fsize,
 	/* Fill the leading characters to make up the desired
 	   width. This may require a '0' if the last character
 	   written was the decimal point. This may also require a '0'
-	   if there are no other characters at all in the ouput. */
+	   if there are no other characters at all in the output. */
       if (fusize > 0) {
 	    while (bp > start_address) {
 		  if (*bp == '.' || strcmp(bp, timeformat_info.suff) == 0)
@@ -1415,7 +1415,7 @@ static unsigned int get_format_char(char **rtn, int ljust, int plus,
           vpi_printf("WARNING: incompatible value for %s%s.\n", info->name,
                      fmtb);
         } else {
-          /* If a width was not giveni, use a width of zero. */
+          /* If a width was not given, use a width of zero. */
           if (width == -1) width = 0;
           if (ljust == 0) sprintf(result, "%*c", width,
                                   value.value.str[strlen(value.value.str)-1]);
@@ -1659,7 +1659,7 @@ static unsigned int get_format_char(char **rtn, int ljust, int plus,
           /* If a width was not given use a width of zero. */
           if (width == -1) width = 0;
           nbits = vpi_get(vpiSize, info->items[*idx]);
-          /* This is 4 chars for all but the last bit (strenght + "_")
+          /* This is 4 chars for all but the last bit (strength + "_")
            * which only needs three chars (strength), but then you need
            * space for the EOS '\0', so it is just number of bits * 4. */
           rsize = nbits*4;
diff --git a/vpi/sys_random.c b/vpi/sys_random.c
index d0a3cb251..41c91d110 100644
--- a/vpi/sys_random.c
+++ b/vpi/sys_random.c
@@ -397,7 +397,7 @@ static PLI_INT32 sys_rand_two_args_compiletf(PLI_BYTE8 *name)
                   break;
             default:
                   vpi_printf("ERROR: %s's seed must be an integer/time"
-                             " varible or a register.\n", name);
+                             " variable or a register.\n", name);
                   vpi_control(vpiFinish, 1);
                   return 0;
       }
@@ -449,7 +449,7 @@ static PLI_INT32 sys_rand_three_args_compiletf(PLI_BYTE8 *name)
                   break;
             default:
                   vpi_printf("ERROR: %s's seed must be an integer/time"
-                             " varible or a register.\n", name);
+                             " variable or a register.\n", name);
                   vpi_control(vpiFinish, 1);
                   return 0;
       }
@@ -484,7 +484,7 @@ static PLI_INT32 sys_random_compiletf(PLI_BYTE8 *name)
                   break;
             default:
                   vpi_printf("ERROR: %s's seed must be an integer/time"
-                             " varible or a register.\n", name);
+                             " variable or a register.\n", name);
                   vpi_control(vpiFinish, 1);
                   return 0;
       }
diff --git a/vpi/sys_readmem.c b/vpi/sys_readmem.c
index a1a252f38..402280c28 100644
--- a/vpi/sys_readmem.c
+++ b/vpi/sys_readmem.c
@@ -445,7 +445,7 @@ static PLI_INT32 sys_writemem_calltf(PLI_BYTE8*name)
       /* Open the data file. */
       file = fopen(path, "w");
       if (file == 0) {
-	    vpi_printf("%s: Unable to open %s for writeing.\n", name, path);
+	    vpi_printf("%s: Unable to open %s for writing.\n", name, path);
 	    free(path);
 	    return 0;
       }
diff --git a/vpi/sys_scanf.c b/vpi/sys_scanf.c
index 14a84adf9..c2b9a4898 100644
--- a/vpi/sys_scanf.c
+++ b/vpi/sys_scanf.c
@@ -250,7 +250,7 @@ static int scan_format(vpiHandle sys, struct byte_source*src, vpiHandle argv)
 	    if (isspace(*fmtp)) {
 		    /* White space matches a string of white space in
 		       the input. The number of spaces is not
-		       relevent, and the match may be 0 or more
+		       relevant, and the match may be 0 or more
 		       spaces. */
 		  while (*fmtp && isspace(*fmtp))
 			fmtp += 1;
diff --git a/vpi/vcd_priv.c b/vpi/vcd_priv.c
index 1f18fd2a3..78d08235e 100644
--- a/vpi/vcd_priv.c
+++ b/vpi/vcd_priv.c
@@ -131,7 +131,7 @@ void vcd_names_sort(struct vcd_names_list_s*tab)
 
    The new signal will be listed as a $var, but no callback
    will be installed.  This saves considerable CPU time and leads
-   to smalle VCD files.
+   to smaller VCD files.
 
    The _vpiNexusId is a private (int) property of IVL simulators.
 */
diff --git a/vpip/vpi_callback.c b/vpip/vpi_callback.c
index e6645153a..baeb22a3f 100644
--- a/vpip/vpi_callback.c
+++ b/vpip/vpi_callback.c
@@ -83,7 +83,7 @@ void vpip_run_value_changes(struct __vpiSignal*sig)
 /*
  * Handle read-only synch events. This causes the callback to be
  * scheduled for a moment at the end of the time period. This method
- * handles scheduling with itme delays.
+ * handles scheduling with time delays.
  */
 static void go_readonly_synch(struct __vpiCallback*rfp)
 {
diff --git a/vvp/README.txt b/vvp/README.txt
index c8bcc8069..b96de8969 100644
--- a/vvp/README.txt
+++ b/vvp/README.txt
@@ -795,7 +795,7 @@ The &PV<> argument is a reference to part of a signal. The syntax is:
 
 The <symbol> is the label for a signal, the <base> is the cannonical
 starting bit of the part select and <width> is the number of bits in
-the select. The second form retreives the <base> from thread space
+the select. The second form retrieves the <base> from thread space
 using <twid> bits starting at <tbase>.
 
 * The T<> argument
diff --git a/vvp/array.cc b/vvp/array.cc
index e0e4ec306..5982d0c6e 100644
--- a/vvp/array.cc
+++ b/vvp/array.cc
@@ -912,7 +912,7 @@ void array_word_change(vvp_array_t array, unsigned long addr)
       for (vvp_fun_arrayport*cur = array->ports_; cur; cur = cur->next_)
 	    cur->check_word_change(addr);
 
-	// Run callbacks attatched to the array itself.
+	// Run callbacks attached to the array itself.
       struct __vpiCallback *next = array->vpi_callbacks;
       struct __vpiCallback *prev = 0;
 
diff --git a/vvp/array.h b/vvp/array.h
index e67832761..d3f79378a 100644
--- a/vvp/array.h
+++ b/vvp/array.h
@@ -43,7 +43,7 @@ extern void array_set_word(vvp_array_t arr,
 			    unsigned off,
 			    vvp_vector4_t val);
 
-extern vvp_vector4_t array_get_word(vvp_array_t array, unsigned adddress);
+extern vvp_vector4_t array_get_word(vvp_array_t array, unsigned address);
 
 /* VPI hooks */
 
diff --git a/vvp/dff.h b/vvp/dff.h
index ea0ef12f1..95593fbdb 100644
--- a/vvp/dff.h
+++ b/vvp/dff.h
@@ -25,7 +25,7 @@
 /*
  * The vvp_dff implements a D-type FF that is agnostic to the data
  * type that is holds. The clock and clock-enable inputs are single
- * bits and may be invertable. An output is propagated on the logical
+ * bits and may be invertible. An output is propagated on the logical
  * rising edge of the clock input, or whenever an asynchronous input
  * is received. Ports are:
  *
diff --git a/vvp/examples/memory.vvp b/vvp/examples/memory.vvp
index d86b78252..4d90b5a10 100644
--- a/vvp/examples/memory.vvp
+++ b/vvp/examples/memory.vvp
@@ -66,7 +66,7 @@ m	.var	"m", 6,0;
 ;;; memory words occupy 8 bits each, that is 7 rounded up to the next
 ;;; multiple of 4.
 
-;;; Four bits ber byte.	 Word fill bits are included.  Commas are
+;;; Four bits per byte.	 Word fill bits are included.  Commas are
 ;;; optional, there may be a comma after the last byte.
 
 	.mem/init memory[20],
diff --git a/vvp/main.cc b/vvp/main.cc
index 94366cf91..2d19e4dd3 100644
--- a/vvp/main.cc
+++ b/vvp/main.cc
@@ -176,7 +176,7 @@ int main(int argc, char*argv[])
                    " -M path        VPI module directory\n"
 		   " -M -           Clear VPI module path\n"
                    " -m module      Load vpi module.\n"
-		   " -n             Non-interctive ($stop = $finish).\n"
+		   " -n             Non-interactive ($stop = $finish).\n"
 		   " -s             $stop right away.\n"
                    " -v             Verbose progress messages.\n" );
            exit(0);
diff --git a/vvp/opcodes.txt b/vvp/opcodes.txt
index a52f6a5a6..f72fe2917 100644
--- a/vvp/opcodes.txt
+++ b/vvp/opcodes.txt
@@ -14,14 +14,14 @@ describes the specific behavior of each opcode, in enough detail
 
 General principles of Arithmetic:
 
-The binary arithmetic instruction in general take three parameters,
+The binary arithmetic instruction in general takes three parameters,
 the left operand, the right operand, and the base. The left operand is
 replaced with the result, which is the same width as the left and
 right operands.
 
 * %abs/wr <bit-o>, <bit-i>
 
-This instructure calculate the absolute value of a real value. It uses
+This instruction calculates the absolute value of a real value. It uses
 the fabs() function in the run-time to do the work.
 
 * %add <bit-l>, <bit-r>, <wid>
@@ -510,7 +510,7 @@ into the destination vector. This is useful for filling a vector.
 
 The %movi variant moves a binary value, LSB first, into the
 destination vector. The immediate value is up to 32bits, padded with
-zeros to fillout the width.
+zeros to fill out the width.
 
 * %mul <bit-l>, <bit-r>, <wid>
 
diff --git a/vvp/vpi_priv.cc b/vvp/vpi_priv.cc
index 79f73fd53..dc0e82a0b 100644
--- a/vvp/vpi_priv.cc
+++ b/vvp/vpi_priv.cc
@@ -906,7 +906,7 @@ vpiHandle vpi_handle_by_name(const char *name, vpiHandle scope)
   the modpath vpiHandle
   
 
-  baiscally, they will redirect the generic vpi_interface
+  basically, they will redirect the generic vpi_interface
   
   vpi_get_delay ( .. )  
   vpi_put_delay ( .. )
diff --git a/vvp/vthread.cc b/vvp/vthread.cc
index 602f4d15f..fa52151b4 100644
--- a/vvp/vthread.cc
+++ b/vvp/vthread.cc
@@ -455,7 +455,7 @@ static void unlink_from_driver(vvp_net_t*src, vvp_net_ptr_t dst_ptr)
 }
 
 /*
- * The CHUNK_LINK instruction is a specla next pointer for linking
+ * The CHUNK_LINK instruction is a special next pointer for linking
  * chunks of code space. It's like a simplified %jmp.
  */
 bool of_CHUNK_LINK(vthread_t thr, vvp_code_t code)
@@ -3903,7 +3903,7 @@ bool of_FORK_UFUNC(vthread_t thr, vvp_code_t cp)
 
 	/* After this function, the .ufunc code has placed an of_JOIN
 	   to pause this thread. Since the child was pushed by the
-	   flag to schecule_vthread, the called function starts up
+	   flag to schedule_vthread, the called function starts up
 	   immediately. */
       return true;
 }
diff --git a/vvp/vvp_island.cc b/vvp/vvp_island.cc
index b44ccbc3e..439afca78 100644
--- a/vvp/vvp_island.cc
+++ b/vvp/vvp_island.cc
@@ -78,7 +78,7 @@ class vvp_island  : private vvp_gen_event_s {
       virtual void run_island() =0;
 
     protected:
-	// The base class collects a list of all the braches in the
+	// The base class collects a list of all the branches in the
 	// island. The derived island class can access this list for
 	// scanning the mesh.
       vvp_island_branch*branches_;
@@ -135,7 +135,7 @@ class vvp_island_port  : public vvp_net_fun_t {
     private:
       vvp_island*island_;
 
-    private: // not imlemented
+    private: // not implemented
       vvp_island_port(const vvp_island_port&);
       vvp_island_port& operator = (const vvp_island_port&);
 };
@@ -157,7 +157,7 @@ static void send_value(vvp_net_t*net, const vvp_vector8_t&val)
 }
 
 /*
-* Branches are connected together to form a mesh of brances. Each
+* Branches are connected together to form a mesh of branches. Each
 * endpoint (there are two) connects circularly to other branch
 * endpoints that are connected together. This list of endpoints forms
 * a node. Thus it is possible for branches to fully specify the mesh
@@ -217,7 +217,7 @@ void vvp_island::flag_island()
 
 /*
 * This method handles the callback from the scheduler. It does basic
-* housecleaning and calles the run_island() method implemented by the
+* housecleaning and calls the run_island() method implemented by the
 * derived class.
 */
 void vvp_island::run_run()
diff --git a/vvp/vvp_net.h b/vvp/vvp_net.h
index 51180d268..fbed7bf09 100644
--- a/vvp/vvp_net.h
+++ b/vvp/vvp_net.h
@@ -198,7 +198,7 @@ class vvp_vector4_t {
 
       void allocate_words_(unsigned size, unsigned long inita, unsigned long initb);
 
-	// Values in the vvp_vector4_t are stored split accross two
+	// Values in the vvp_vector4_t are stored split across two
 	// arrays. For each bit in the vector, there is an abit and a
 	// bbit. the encoding of a vvp_vector4_t is:
 	//