Systems and methods for distinguishing among human users and software robots

1. A system, comprising:

at least one computer; and

at least one non-transitory computer-readable storage medium storing processor-executable instructions that, when executed by the at least one computer, cause the at least one computer to perform:

receiving, via at least one network, a first communication from a device different from the at least one computer;

identifying, from the first communication, a request to access a web resource;

generating a webpage comprising:

location information representing a challenge text, the location information identifying a plurality of webpage locations at which to display a plurality of graphical elements having a different visual appearance from a background of the webpage in order to display a visual representation of the challenge text, the location information comprising coordinates for at least some of the plurality of webpage locations; and

software code that, when executed by an Internet browser, causes the Internet browser, when rendering the webpage, to display the visual representation of the challenge text at least in part by displaying the plurality of graphical elements at the plurality of webpage locations, wherein the plurality of graphical elements comprises HTML elements and/or OpenGL elements;

transmitting, via the at least one network, the webpage to the device;

receiving, via the at least one network, a second communication from the device;

identifying, from the second communication, a response text; and

providing the device with access to the web resource when a number of errors between the challenge text and the response text is less than a threshold number of errors.

2. The system of claim 1 , wherein the location information does not include an image.

3. The system of claim 1 , wherein the processor-executable instructions, when executed, further cause the at least one computer to perform:

generating the software code and the location information.

4. The system of claim 1 , wherein the software code, when executed by the Internet browser, causes the Internet browser to display the visual representation at least in part by displaying a plurality of span elements at the plurality of webpage locations.

5. The system of claim 1 , wherein the software code, when executed by the Internet browser, causes the Internet browser to display the visual representation at least in part by displaying a plurality of HTML canvas elements at the plurality of webpage locations.

6. The system of claim 1 , wherein the software code includes OpenGL instructions, and wherein the software code, when executed by the Internet browser, causes the Internet browser to display the visual representation at least in part by using at least one graphical processing unit (GPU) to execute the OpenGL instructions to render the plurality of graphical elements.

7. The system of claim 1 , wherein the software code, when executed by the Internet browser, sets a color of at least one of the plurality of graphical elements to a color different from a background color of the webpage.

8. The system of claim 1 , wherein the software code, when executed by the Internet browser, sets a color of at least one of the plurality of graphical elements to a first color at a first time and sets the color of the at least one of the plurality of graphical elements to a second color at a second time different from the first time, wherein the first color is different from the second color.

9. The system of claim 1 , wherein the software code, when executed by the Internet browser, causes a first text to be displayed and subsequently causes the challenge text to be displayed after a threshold amount of time, wherein the first text is different from the challenge text.

10. The system of claim 1 , wherein the processor-executable instructions further cause the at least one computer to perform:

identifying a challenge token from the second communication; and

validating the second communication using the challenge token.

11. A method, performed by at least one computer, the method comprising:

receiving, via at least one network, a first communication from a device different from the at least one computer;

identifying, from the first communication, a request to access a web resource;

generating a webpage comprising:

location information representing a challenge text, the location information identifying a plurality of webpage locations at which to display a plurality of graphical elements having a different visual appearance from a background of the webpage in order to display a visual representation of the challenge text, the location information comprising coordinates for at least some of the plurality of webpage locations; and

software code that, when executed by an Internet browser, causes the Internet browser, when rendering the webpage, to display the visual representation of the challenge text at least in part by displaying the plurality of graphical elements at the plurality of webpage locations, wherein the plurality of graphical elements comprises HTML elements and/or OpenGL elements;

transmitting, via the at least one network, the webpage to the device;

receiving, via the at least one network, a second communication from the device;

identifying, from the second communication, a response text; and

providing the device with access to the web resource when a number of errors between the challenge text and the response text is less than a threshold number of errors.

12. The method of claim 11 , further comprising:

generating the software code and the location information.

13. The method of claim 11 , wherein the software code, when executed by the Internet browser, causes the Internet browser to display the visual representation at least in part by displaying a plurality of span elements at the plurality of webpage locations.

14. The method of claim 11 , wherein the software code, when executed by the Internet browser, causes the Internet browser to display the visual representation at least in part by displaying a plurality of HTML canvas elements at the plurality of webpage locations.

15. The method of claim 11 , wherein the software code includes OpenGL instructions, and wherein the software code, when executed by the Internet browser, causes the Internet browser to display the visual representation at least in part by using at least one graphical processing unit (GPU) to execute the OpenGL instructions to render the plurality of graphical elements.

16. The method of claim 11 , wherein the software code, when executed by the Internet browser, causes the webpage to initially display a first text and subsequently display the challenge text after a threshold amount of time, wherein the first text is different from the challenge text.

17. At least one non-transitory computer-readable storage medium storing processor-executable instructions that, when executed by at least one computer, cause the at least one computer to perform:

receiving, via at least one network, a first communication from a device different from the at least one computer;

identifying, from the first communication, a request to access a web resource;

generating a webpage comprising:

location information representing a challenge text, the location information identifying a plurality of webpage locations at which to display a plurality of graphical elements having a different visual appearance from a background of the webpage in order to display a visual representation of the challenge text, the location information comprising coordinates for at least some of the plurality of webpage locations; and

software code that, when executed by an Internet browser, causes the Internet browser, when rendering the webpage, to display the visual representation of the challenge text at least in part by displaying the plurality of graphical elements at the plurality of webpage locations, wherein the plurality of graphical elements comprises HTML elements and/or OpenGL elements;

transmitting, via the at least one network, the webpage to the device

receiving, via the at least one network, a second communication from the device;

identifying, from the second communication, a response text; and

providing the device with access to the web resource when a number of errors between the challenge text and the response text is less than a threshold number of errors.

18. The at least one non-transitory computer readable storage medium of claim 17 , wherein the processor-executable instructions, when executed, further cause the at least one computer to perform:

generating the software code and the location information.

19. The at least one non-transitory computer readable storage medium of claim 17 , wherein the software code, when executed by the Internet browser, causes the Internet browser to display the visual representation at least in part by displaying a plurality of span elements at the plurality of webpage locations.

20. The at least one non-transitory computer readable storage medium of claim 17 , wherein the software code, when executed by the Internet browser, causes the Internet browser to display the visual representation at least in part by displaying a plurality of HTML canvas elements at the plurality of webpage locations.

21. The at least one non-transitory computer readable storage medium of claim 17 , wherein the software code includes OpenGL instructions, and wherein the software code, when executed by the Internet browser, causes the Internet browser to display the visual representation at least in part by using at least one graphical processing unit (GPU) to execute the OpenGL instructions to render the plurality of graphical elements.

22. The at least one non-transitory computer readable storage medium of claim 17 , wherein the software code, when executed by the Internet browser, sets a color of at least one of the plurality of graphical elements to a color different from a background color of the webpage.

23. The at least one non-transitory computer readable storage medium of claim 17 , wherein the software code, when executed by the Internet browser, sets a color of at least one of the plurality of graphical elements to a first color at a first time and sets the color of the at least one of the plurality of graphical elements to a second color at a second time different from the first time, wherein the first color is different from the second color.

24. The at least one non-transitory computer readable storage medium of claim 17 , wherein the software code, when executed by the Internet browser, causes a first text to be displayed and subsequently causes the challenge text to be displayed after a threshold amount of time, wherein the first text is different from the challenge text.

25. The at least one non-transitory computer readable storage medium of claim 17 , wherein the processor-executable instructions further cause the at least one computer to perform:

identifying a challenge token from the second communication; and

validating the second communication using the challenge token.