diff --git a/InvalidResult.ts b/InvalidResult.ts
new file mode 100644
index 0000000..62f626d
--- /dev/null
+++ b/InvalidResult.ts
@@ -0,0 +1,33 @@
+//typescriptClasses/InvalidResult.ts
+//Matthew Ellison
+// Created: 10-18-20
+//Modified: 10-18-20
+//This file contains a class that is used to time the execution time of other programs
+/*
+Copyright (C) 2020  Matthew Ellison
+
+	This program is free software: you can redistribute it and/or modify
+	it under the terms of the GNU Lesser General Public License as published by
+	the Free Software Foundation, either version 3 of the License, or
+	(at your option) any later version.
+
+	This program is distributed in the hope that it will be useful,
+	but WITHOUT ANY WARRANTY; without even the implied warranty of
+	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+	GNU Lesser General Public License for more details.
+
+	You should have received a copy of the GNU Lesser General Public License
+	along with this program.  If not, see <https://www.gnu.org/licenses/>.
+*/
+
+
+export class InvalidResult{
+	private message: string;
+	public constructor(message: string){
+		this.message = message;
+	
+	}
+	public getMessage(): string{
+		return this.message;
+	}
+}
diff --git a/Stopwatch.ts b/Stopwatch.ts
new file mode 100644
index 0000000..967af2c
--- /dev/null
+++ b/Stopwatch.ts
@@ -0,0 +1,143 @@
+//typescriptClasses/Stopwatch.ts
+//Matthew Ellison
+// Created: 10-18-20
+//Modified: 10-18-20
+//This file contains a class that is used to time the execution time of other programs
+/*
+Copyright (C) 2020  Matthew Ellison
+
+	This program is free software: you can redistribute it and/or modify
+	it under the terms of the GNU Lesser General Public License as published by
+	the Free Software Foundation, either version 3 of the License, or
+	(at your option) any later version.
+
+	This program is distributed in the hope that it will be useful,
+	but WITHOUT ANY WARRANTY; without even the implied warranty of
+	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+	GNU Lesser General Public License for more details.
+
+	You should have received a copy of the GNU Lesser General Public License
+	along with this program.  If not, see <https://www.gnu.org/licenses/>.
+*/
+
+
+import {InvalidResult} from "./InvalidResult";
+import {performance} from "perf_hooks";
+
+
+//An enum that helps keep track of how many times the time has been reduced in the getStr function
+enum TIME_RESOLUTION{ NANOSECOND, MICROSECOND, MILLISECOND, SECOND, MINUTE, HOUR, ERROR };
+
+export class Stopwatch{
+	private startTime: number;
+	private stopTime: number;
+	//Constructor makes sure all values are set to defaults
+	public constructor(){
+		//Make sure both values are null so it is easier to detect incorrect function calling order
+		this.startTime = null;
+		this.stopTime = null;
+	}
+	//Returns a long with the elapsed time in milliseconds. Used by other functions to get the time before converting it to the correct resolution
+	private getTime(): number{
+		if(this.startTime == null){
+			return 0;
+		}
+		else if(this.stopTime == null){
+			return performance.now() - this.startTime;
+		}
+		else{
+			return this.stopTime - this.startTime;
+		}
+	}
+	//Simultates starting a stopwatch by saving the time
+	public start(): void{
+		//Make sure the stop time is reset
+		this.stopTime = null;
+		//Get the time as close to returning from the function as possible
+		this.startTime = performance.now();
+	}
+	//Simulates stopping a stopwatch by saving the time
+	public stop(): void{
+		//Set the stopTime as close to call time as possible
+		this.stopTime = performance.now();
+		//If the startTime has not been set then reset stopTime
+		if(this.startTime == null){
+			this.stopTime = null;
+		}
+	}
+	//Resets all variables in the stopwatch
+	public reset(): void{
+		//Make sure all variables are reset correctly
+		this.startTime = null;
+		this.stopTime = null;
+	}
+	//Returns the time in nanoseconds
+	public getNano(): number{
+		return this.getTime() * 1000000;
+	}
+	//Returns the time in microseconds
+	public getMicro(): number{
+		return this.getTime() * 1000;
+	}
+	//Returns the time in milliseconds
+	public getMilli(): number{
+		return this.getTime();
+	}
+	//Returns the time in seconds
+	public getSecond(): number{
+		return this.getTime() / 1000;
+	}
+	//Returns the time in minutes
+	public getMinute(): number{
+		return this.getTime() / 60000;
+	}
+	//Returns the time in hours
+	public getHour(): number{
+		return this.getTime() / 3600000;
+	}
+	//Returns the time as a string at the 'best' resolution. (Goal is xxx.xxx)
+	public getStr(): string{
+		//Get the current duraction from time
+		return Stopwatch.getStr(this.getNano());
+	}
+
+	public static getStr(nanoseconds: number): string{
+		let duration: number = nanoseconds;
+		//Reduce the num,ber to the appropriate number of digits. (xxx.x).
+		//This loop works down to seconds
+		let resolution: TIME_RESOLUTION;
+		for(resolution = TIME_RESOLUTION.NANOSECOND;(resolution < TIME_RESOLUTION.SECOND) && (duration >= 1000);++resolution){
+			duration /= 1000;
+		}
+		//Check if the duration needs reduced to minutes
+		if((duration >= 120) && (resolution == TIME_RESOLUTION.SECOND)){
+			//Reduce to minutes
+			duration /= 60;
+			++resolution;
+
+			//Check if the duration needs reduced to hours
+			if(duration >= 60){
+				//Reduce to hours
+				duration /= 60;
+				++resolution;
+			}
+		}
+
+		//Turn the number into a string
+		let time: string = duration.toFixed(3);
+
+		//Tack on the appropriate suffix for resolution
+		switch(resolution){
+			case TIME_RESOLUTION.NANOSECOND: time += " nanoseconds"; break;
+			case TIME_RESOLUTION.MICROSECOND: time += " microseconds"; break;
+			case TIME_RESOLUTION.MILLISECOND: time += " milliseconds"; break;
+			case TIME_RESOLUTION.SECOND: time += " seconds"; break;
+			case TIME_RESOLUTION.MINUTE: time += " minutes"; break;
+			case TIME_RESOLUTION.HOUR: time += " hours"; break;
+			case TIME_RESOLUTION.ERROR:
+			default: throw new InvalidResult("timeResolution was invalid");
+		}
+		//Return the string
+		return time;
+	}
+}
diff --git a/TestStopwatch.ts b/TestStopwatch.ts
new file mode 100644
index 0000000..f138c17
--- /dev/null
+++ b/TestStopwatch.ts
@@ -0,0 +1,99 @@
+//typescriptClasses/TestStopwatch.ts
+//Matthew Ellison
+// Created: 10-18-20
+//Modified: 10-18-20
+//This file contains a class that is used to time the execution time of other programs
+/*
+Copyright (C) 2020  Matthew Ellison
+
+	This program is free software: you can redistribute it and/or modify
+	it under the terms of the GNU Lesser General Public License as published by
+	the Free Software Foundation, either version 3 of the License, or
+	(at your option) any later version.
+
+	This program is distributed in the hope that it will be useful,
+	but WITHOUT ANY WARRANTY; without even the implied warranty of
+	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+	GNU Lesser General Public License for more details.
+
+	You should have received a copy of the GNU Lesser General Public License
+	along with this program.  If not, see <https://www.gnu.org/licenses/>.
+*/
+
+
+import assert = require("assert");
+import {Stopwatch} from "./Stopwatch";
+
+
+let NUM_TO_RUN = 100000;
+
+function testStartStop(): void{
+	let timer: Stopwatch = new Stopwatch();
+	timer.start();
+	timer.stop();
+	//If it gets to here without throwing an exception everything went well
+	console.log("start/stop passed");
+}
+function testConversion(): void{
+	let timer: Stopwatch = new Stopwatch();
+	let sum: number = 0;
+	//Start the timer
+	timer.start();
+	//Do something to run some time
+	for(let cnt: number = 0;cnt < NUM_TO_RUN;++cnt){
+		sum += cnt;
+	}
+	//Stop the timer
+	timer.stop();
+	//Assert something so the sum isn't ignored during compile
+	assert.notStrictEqual(sum, 0, "You really messed up");
+	//Check that the different resolutions work out correctly
+	let nano: number = timer.getNano();
+	assert.strictEqual(timer.getMicro(), nano / 1000, "Micro resolution test failed");
+	assert.strictEqual(timer.getMilli(), nano / 1000000, "Milli resolution test failed");
+	assert.strictEqual(timer.getSecond(), nano / 1000000000, "Minute resolution test failed");
+	assert.strictEqual(timer.getMinute(), nano / 60000000000, "Minute resolution test failed");
+	assert.strictEqual(timer.getHour(), nano / 3600000000000, "Hour resolution test failed");
+	console.log("conversion passed");
+}
+function testStringConversion(): void{
+	//Test nanoseconds
+	let results: string = Stopwatch.getStr(1.0);
+	assert.strictEqual(results, "1.000 nanoseconds", "String conversion to nanoseconds failed");
+	//Test microseconds
+	results = Stopwatch.getStr(1.0e3);
+	assert.strictEqual(results, "1.000 microseconds", "String conversion to microseconds failed");
+	//Test milliseconds
+	results = Stopwatch.getStr(1.0e6);
+	assert.strictEqual(results, "1.000 milliseconds", "String conversion to milliseconds failed");
+	//Test seconds
+	results = Stopwatch.getStr(1.0e9);
+	assert.strictEqual(results, "1.000 seconds", "String conversion to seconds failed");
+	//Test mintues
+	results = Stopwatch.getStr(1.0e12);
+	assert.strictEqual(results, "16.667 minutes", "String conversion to minutes failed");
+	//Rest hours
+	results = Stopwatch.getStr(1.0e13);
+	assert.strictEqual(results, "2.778 hours", "String conversion to hours failed");
+	console.log("string conversion passed");
+}
+
+//Run the functions
+try{
+	testStartStop();
+}
+catch(error){
+	console.error("start/stop test failed!");
+}
+try{
+	testConversion();
+}
+catch(error){
+	console.error("conversion test failed!");
+}
+try{
+	testStringConversion();
+}
+catch(error){
+	console.error("string conversion test failed!");
+}