Gear System To Increase a DC Motor Torque

A Few days ago, i wrote about a job to made a line follower. After i was making the job, i was getting problem. To making the line follower, i was using dc motor. But, i was geting problem with torque from it. The DC motor is used can't give me enouh torque. i am confused about how to increase torque it. i was thingking about it. And i was remember about search engine, why i am not looking how to incresae torque from a dc motor at search engine ??? And then, i am looking from search engine about how to increase dc motor torque. i was founding solution about how to increase torque it. To increase it, we can use system gear. But, i am confuse how to aplication sistem gear at my line follower. 

After reading some article about torque, dc motor, and gear system. I was get some new information about it. There are some dc motor's where the motor have been equipped with gear system. But i  am get forget about the name. that motor have been already with gear system to increase torque from motor, with this gear system, this can make motor have more torque, motor can bring more load. 

Very pleasue, i am getting information about how to increase torque from a dc motor, and finnaly, i am getting to update artcle on this blog about how to increase torque from dc motor. And i hope, this article can helping people who have the same problem about how to increase dc motor torque. Thanks