diff --git a/contrib/apps/httpserver/httpserver-netconn.c b/contrib/apps/httpserver/httpserver-netconn.c
index 26976bf8..36f5ad85 100644
--- a/contrib/apps/httpserver/httpserver-netconn.c
+++ b/contrib/apps/httpserver/httpserver-netconn.c
@@ -40,7 +40,7 @@ http_server_netconn_serve(struct netconn *conn)
         buf[4]=='/' ) {
 
       /* Send the HTML header
-             * subtract 1 from the size, since we dont send the \0 in the string
+             * subtract 1 from the size, since we don't send the \0 in the string
              * NETCONN_NOCOPY: our data is const static, so no need to copy it
        */
       netconn_write(conn, http_html_hdr, sizeof(http_html_hdr)-1, NETCONN_NOCOPY);
diff --git a/contrib/ports/unix/lib/lwipopts.h b/contrib/ports/unix/lib/lwipopts.h
index 34d3a8cf..231fc779 100644
--- a/contrib/ports/unix/lib/lwipopts.h
+++ b/contrib/ports/unix/lib/lwipopts.h
@@ -40,7 +40,7 @@
 
 /*
  * Include user defined options first. Anything not defined in these files
- * will be set to standard values. Override anything you dont like!
+ * will be set to standard values. Override anything you don't like!
  */
 #include "lwipopts.h"
 #include "lwip/debug.h"
diff --git a/contrib/ports/unix/port/netif/sio.c b/contrib/ports/unix/port/netif/sio.c
index 185a4eca..b33e6752 100644
--- a/contrib/ports/unix/port/netif/sio.c
+++ b/contrib/ports/unix/port/netif/sio.c
@@ -66,7 +66,7 @@
 #define FALSE 0
 #endif
 
-/* for all of you who dont define SIO_DEBUG in debug.h */
+/* for all of you who don't define SIO_DEBUG in debug.h */
 #ifndef SIO_DEBUG
 #define SIO_DEBUG 0
 #endif
diff --git a/doc/ZeroCopyRx.c b/doc/ZeroCopyRx.c
index 0e8219bd..600b13a0 100644
--- a/doc/ZeroCopyRx.c
+++ b/doc/ZeroCopyRx.c
@@ -13,7 +13,7 @@ void my_pbuf_free_custom(void* p)
   my_custom_pbuf_t* my_puf = (my_custom_pbuf_t*)p;
 
   // invalidate data cache here - lwIP and/or application may have written into buffer!
-  // (invalidate is faster than flushing, and noone needs the correct data in the buffer)
+  // (invalidate is faster than flushing, and no one needs the correct data in the buffer)
   invalidate_cpu_cache(p->payload, p->tot_len);
 
   SYS_ARCH_PROTECT(old_level);
diff --git a/doc/doxygen/main_page.h b/doc/doxygen/main_page.h
index 4301c72f..4766c3a1 100644
--- a/doc/doxygen/main_page.h
+++ b/doc/doxygen/main_page.h
@@ -147,7 +147,7 @@
  * -------------
  * In mainloop mode, only @ref callbackstyle_api can be used.
  * The user has two possibilities to ensure there is only one
- * exection context at a time in lwIP:
+ * execution context at a time in lwIP:
  *
  * 1) Deliver RX ethernet packets directly in interrupt context to lwIP
  *    by calling netif->input directly in interrupt. This implies all lwIP
@@ -181,7 +181,7 @@
  *    it is safe to call any @ref callbackstyle_api from there.
  *
  * 2) Use @ref LWIP_TCPIP_CORE_LOCKING. All @ref callbackstyle_api
- *    functions can be called when lwIP core lock is aquired, see
+ *    functions can be called when lwIP core lock is acquired, see
  *    @ref LOCK_TCPIP_CORE() and @ref UNLOCK_TCPIP_CORE().
  *    These macros cannot be used in an interrupt context!
  *    Note the OS must correctly handle priority inversion for this.
@@ -258,7 +258,7 @@
  */
 
 /**
- * @page sys_init System initalization
+ * @page sys_init System initialization
 A truly complete and generic sequence for initializing the lwIP stack
 cannot be given because it depends on additional initializations for
 your runtime environment (e.g. timers).
@@ -343,7 +343,7 @@ Call these functions in the order of appearance:
  * - sockets.h
  * - sys.h
  *
- * Additionaly, memory (de-)allocation functions may be
+ * Additionally, memory (de-)allocation functions may be
  * called from multiple threads (not ISR!) with NO_SYS=0
  * since they are protected by @ref SYS_LIGHTWEIGHT_PROT and/or
  * semaphores.
diff --git a/doc/mqtt_client.txt b/doc/mqtt_client.txt
index 1e039815..d189a352 100644
--- a/doc/mqtt_client.txt
+++ b/doc/mqtt_client.txt
@@ -150,7 +150,7 @@ void example_publish(mqtt_client_t *client, void *arg)
   }
 }
 
-/* Called when publish is complete either with sucess or failure */
+/* Called when publish is complete either with success or failure */
 static void mqtt_pub_request_cb(void *arg, err_t result)
 {
   if(result != ERR_OK) {
diff --git a/doc/ppp.txt b/doc/ppp.txt
index 8b88b3a6..797b4e0a 100644
--- a/doc/ppp.txt
+++ b/doc/ppp.txt
@@ -404,7 +404,7 @@ really know what you are doing, your move ;-)
 
 
 /*
- * Fonction to call for received data
+ * Function to call for received data
  *
  * ppp, PPP control block
  * buffer, input buffer
diff --git a/src/apps/mdns/mdns_domain.c b/src/apps/mdns/mdns_domain.c
index 47934eff..265b5e6a 100644
--- a/src/apps/mdns/mdns_domain.c
+++ b/src/apps/mdns/mdns_domain.c
@@ -227,7 +227,7 @@ mdns_readname_loop(struct pbuf *p, u16_t offset, struct mdns_domain *domain, uns
         u16_t res;
         /* Recursive call, maximum depth will be checked */
         res = mdns_readname_loop(p, jumpaddr, domain, depth + 1);
-        /* Dont return offset since new bytes were not read (jumped to somewhere in packet) */
+        /* Don't return offset since new bytes were not read (jumped to somewhere in packet) */
         if (res == MDNS_READNAME_ERROR) {
           return res;
         }
diff --git a/src/apps/mdns/mdns_out.c b/src/apps/mdns/mdns_out.c
index 776af804..5c6d26b7 100644
--- a/src/apps/mdns/mdns_out.c
+++ b/src/apps/mdns/mdns_out.c
@@ -1080,7 +1080,7 @@ mdns_start_multicast_timeouts_ipv6(struct netif *netif)
 /**
  *  This function clears the output message without changing the destination
  *  address or port. This is useful for clearing the delayed msg structs without
- *  loosing the set IP.
+ *  losing the set IP.
  *
  *  @param outmsg pointer to output message to clear.
  */
diff --git a/src/core/ipv4/etharp.c b/src/core/ipv4/etharp.c
index 26dde61c..5ff24768 100644
--- a/src/core/ipv4/etharp.c
+++ b/src/core/ipv4/etharp.c
@@ -142,7 +142,7 @@ static err_t etharp_raw(struct netif *netif,
 /**
  * Free a complete queue of etharp entries
  *
- * @param q a qeueue of etharp_q_entry's to free
+ * @param q a queue of etharp_q_entry's to free
  */
 static void
 free_etharp_q(struct etharp_q_entry *q)
diff --git a/src/core/mem.c b/src/core/mem.c
index 315fb3c5..8566edce 100644
--- a/src/core/mem.c
+++ b/src/core/mem.c
@@ -688,7 +688,7 @@ mem_free(void *rmem)
 /**
  * Shrink memory returned by mem_malloc().
  *
- * @param rmem pointer to memory allocated by mem_malloc the is to be shrinked
+ * @param rmem pointer to memory allocated by mem_malloc the is to be shrunk
  * @param new_size required size after shrinking (needs to be smaller than or
  *                equal to the previous size)
  * @return for compatibility reasons: is always == rmem, at the moment
@@ -757,7 +757,7 @@ mem_trim(void *rmem, mem_size_t new_size)
     LWIP_ASSERT("invalid next ptr", mem->next != MEM_SIZE_ALIGNED);
     /* remember the old next pointer */
     next = mem2->next;
-    /* create new struct mem which is moved directly after the shrinked mem */
+    /* create new struct mem which is moved directly after the shrunk mem */
     ptr2 = (mem_size_t)(ptr + SIZEOF_STRUCT_MEM + newsize);
     if (lfree == mem2) {
       lfree = ptr_to_mem(ptr2);
diff --git a/src/core/netif.c b/src/core/netif.c
index a4b5bf61..a580c86f 100644
--- a/src/core/netif.c
+++ b/src/core/netif.c
@@ -741,7 +741,7 @@ netif_set_addr(struct netif *netif, const ip4_addr_t *ipaddr, const ip4_addr_t *
     change_reason |= LWIP_NSC_IPV4_SETTINGS_CHANGED;
   }
   if (!remove) {
-    /* Isssue a callback even if the address hasn't changed, eg. DHCP reboot */
+    /* Issue a callback even if the address hasn't changed, eg. DHCP reboot */
     change_reason |= LWIP_NSC_IPV4_ADDR_VALID;
   }
   if (change_reason != LWIP_NSC_NONE) {
diff --git a/src/core/tcp.c b/src/core/tcp.c
index b1481792..5a62c556 100644
--- a/src/core/tcp.c
+++ b/src/core/tcp.c
@@ -1062,7 +1062,7 @@ again:
  * @param ipaddr the remote ip address to connect to
  * @param port the remote tcp port to connect to
  * @param connected callback function to call when connected (on error,
-                    the err calback will be called)
+                    the err callback will be called)
  * @return ERR_VAL if invalid arguments are given
  *         ERR_OK if connect request has been sent
  *         other err_t values if connect request couldn't be sent
diff --git a/src/include/netif/ppp/eap.h b/src/include/netif/ppp/eap.h
index 3ee9aaf8..32434ed5 100644
--- a/src/include/netif/ppp/eap.h
+++ b/src/include/netif/ppp/eap.h
@@ -13,7 +13,7 @@
  *
  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
- * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  *
  * Original version by James Carlson
  *
diff --git a/src/include/netif/ppp/vj.h b/src/include/netif/ppp/vj.h
index 77d9976c..4e6601c1 100644
--- a/src/include/netif/ppp/vj.h
+++ b/src/include/netif/ppp/vj.h
@@ -16,7 +16,7 @@
  * from this software without specific prior written permission.
  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
- * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  *
  * Van Jacobson (van@helios.ee.lbl.gov), Dec 31, 1989:
  * - Initial distribution.
diff --git a/src/netif/lowpan6.c b/src/netif/lowpan6.c
index 8479be40..9eb47b9c 100644
--- a/src/netif/lowpan6.c
+++ b/src/netif/lowpan6.c
@@ -605,8 +605,8 @@ lowpan6_output(struct netif *netif, struct pbuf *q, const ip6_addr_t *ip6addr)
 
 #if LWIP_6LOWPAN_INFER_SHORT_ADDRESS
   if (src.addr_len == 2) {
-    /* If source address was compressable to short_mac_addr, and dest has same subnet and
-     * is also compressable to 2-bytes, assume we can infer dest as a short address too. */
+    /* If source address was compressible to short_mac_addr, and dest has same subnet and
+     * is also compressible to 2-bytes, assume we can infer dest as a short address too. */
     dest.addr_len = 2;
     dest.addr[0] = ((u8_t *)q->payload)[38];
     dest.addr[1] = ((u8_t *)q->payload)[39];
diff --git a/src/netif/lowpan6_common.c b/src/netif/lowpan6_common.c
index 89758d94..cd468942 100644
--- a/src/netif/lowpan6_common.c
+++ b/src/netif/lowpan6_common.c
@@ -523,7 +523,7 @@ lowpan6_decompress_hdr(u8_t *lowpan6_buffer, size_t lowpan6_bufsize,
       lowpan6_offset += 2;
     } else if ((lowpan6_buffer[1] & 0x30) == 0x30) {
       LWIP_DEBUGF(LWIP_LOWPAN6_DECOMPRESSION_DEBUG, ("SAM == 11, src compression, 0bits inline, using other headers\n"));
-      /* no information avalaible, using other layers, see RFC6282 ch 3.2.2 */
+      /* no information available, using other layers, see RFC6282 ch 3.2.2 */
       ip6hdr->src.addr[0] = PP_HTONL(0xfe800000UL);
       ip6hdr->src.addr[1] = 0;
       if (src->addr_len == 2) {
diff --git a/src/netif/ppp/eap.c b/src/netif/ppp/eap.c
index 3aa39790..7ff52b45 100644
--- a/src/netif/ppp/eap.c
+++ b/src/netif/ppp/eap.c
@@ -13,7 +13,7 @@
  *
  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
- * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  *
  * Original version by James Carlson
  *
diff --git a/src/netif/ppp/ipcp.c b/src/netif/ppp/ipcp.c
index 9ce98512..b033cde0 100644
--- a/src/netif/ppp/ipcp.c
+++ b/src/netif/ppp/ipcp.c
@@ -1067,7 +1067,7 @@ bad:
  * ipcp_nakci - Peer has sent a NAK for some of our CIs.
  * This should not modify any state if the Nak is bad
  * or if IPCP is in the OPENED state.
- * Calback from fsm_rconfnakrej - Receive Configure-Nak or Configure-Reject.
+ * Callback from fsm_rconfnakrej - Receive Configure-Nak or Configure-Reject.
  *
  * Returns:
  *	0 - Nak was bad.
@@ -1739,7 +1739,7 @@ static int ipcp_reqci(fsm *f, u_char *inp, int *len, int reject_if_disagree) {
 	}
 endswitch:
 	if (orc == CONFACK &&		/* Good CI */
-	    rc != CONFACK)		/*  but prior CI wasnt? */
+	    rc != CONFACK)		/*  but prior CI wasn't? */
 	    continue;			/* Don't send this one */
 
 	if (orc == CONFNAK) {		/* Nak this CI? */
diff --git a/src/netif/ppp/lcp.c b/src/netif/ppp/lcp.c
index 63ea23a5..e77ec401 100644
--- a/src/netif/ppp/lcp.c
+++ b/src/netif/ppp/lcp.c
@@ -2232,7 +2232,7 @@ static int lcp_reqci(fsm *f, u_char *inp, int *lenp, int reject_if_disagree) {
 
 endswitch:
 	if (orc == CONFACK &&		/* Good CI */
-	    rc != CONFACK)		/*  but prior CI wasnt? */
+	    rc != CONFACK)		/*  but prior CI wasn't? */
 	    continue;			/* Don't send this one */
 
 	if (orc == CONFNAK) {		/* Nak this CI? */
diff --git a/src/netif/ppp/vj.c b/src/netif/ppp/vj.c
index 3fecba69..b322ee4a 100644
--- a/src/netif/ppp/vj.c
+++ b/src/netif/ppp/vj.c
@@ -15,7 +15,7 @@
  * from this software without specific prior written permission.
  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
- * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  *
  * Van Jacobson (van@helios.ee.lbl.gov), Dec 31, 1989:
  *   Initial distribution.
diff --git a/test/unit/mdns/test_mdns.c b/test/unit/mdns/test_mdns.c
index 5a630f47..01434b5d 100644
--- a/test/unit/mdns/test_mdns.c
+++ b/test/unit/mdns/test_mdns.c
@@ -830,7 +830,7 @@ START_TEST(compress_jump_to_jump)
 
   offset = 0x20;
   length = mdns_compress_domain(p, &offset, &domain);
-  /* Dont compress if jump would be to a jump */
+  /* Don't compress if jump would be to a jump */
   fail_unless(length == domain.length);
 
   offset = 0x10;