Update README.md

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README.md

@@ -6,7 +6,7 @@ Hardware specific <a href="http://github.com/mathworks/thingspeak-arduino/tree/m
 
 ThingSpeak offers free data storage and analysis of time-stamped numeric or alphanumeric data. Users can access ThingSpeak by visiting http://thingspeak.com and creating a ThingSpeak user account.
 
-ThingSpeak stores data in channels. Channels support an unlimited number of timestamped observations (think of these as rows in a spreadsheet). Each channel has up to 8 fields (think of these as columns in a speadsheet). Check out this [video](http://www.mathworks.com/videos/introduction-to-thingspeak-107749.html) for an overview.
+ThingSpeak stores data in channels. Channels support an unlimited number of timestamped observations (think of these as rows in a spreadsheet). Each channel has up to 8 fields (think of these as columns in a speadsheet). Check out this [video](https://www.mathworks.com/videos/introduction-to-thingspeak-107749.html) for an overview.
 
 Channels may be public, where anyone can see the data, or private, where only the owner and select users can read the data. Each channel has an associated Write API Key that is used to control who can write to a channel. In addition, private channels have one or more Read API Keys to control who can read from private channel. An API Key is not required to read from public channels.  Each channel can have up to 8 fields. One field is created by default.