Inline and contextual delivery of database content

1. A method performed by one or more computers, the method comprising:

storing, by the one or more computers, records that specify a set of terms and records that indicate entities corresponding to the respective terms;

receiving, by the one or more computers, a message from a client device over a communication network, wherein the message is sent in response to a determination that a particular term from the set of terms occurs in text of a user interface of the client device, and wherein the message from the client device indicates the particular term from the set of terms that is determined to occur in the text of the user interface of the client device;

in response to receiving the message from the client device:

using, by the one or more computers, the stored records to identify a particular entity corresponding to the particular term indicated in the message from the client device;

identifying, by the one or more computers, one or more attributes of the particular entity using a semantic graph, wherein identifying the one or more attributes of the particular entity comprises:

determining, using the semantic graph, an entity type of the particular entity;

selecting, from among information card templates for different entity types, an information card template for the determined entity type, wherein the selected information card template specifies a predetermined subset of attributes of entities of the determined entity type; and

identifying the predetermined subset of attributes specified by the selected information card template as the one or more attributes; and

retrieving, by the one or more computers, values for the one or more attributes of the particular entity from a database, including retrieving a value for each of the attributes in the predetermined subset of attributes; and

responding, by the one or more computers, to the message from the client device by sending a response message to the client device over the communication network, wherein the response message identifies the one or more attributes of the particular entity and includes the retrieved values for the one or more attributes of the particular entity, wherein the response message includes the retrieved values for the attributes in the predetermined subset of attributes.

2. The method of claim 1 , wherein sending the response message to the client device comprises providing information card data defining an information card to be presented by the client device in response to user interaction with the particular term, wherein the information card data is provided to the client device over the network before a user of the client device interacts with the particular term in the user interface of the client device.

3. The method of claim 1 , further comprising providing the set of terms to the client device over the communication network; and

wherein receiving the message comprises receiving a message sent by the client device in response to the client device determining that the particular term from the set of terms is included in the text of the user interface of the client device.

4. The method of claim 1 , wherein the message from the client device indicates keywords included in the text of the user interface of the client device in addition to the particular term; and

wherein the method includes selecting, from among keywords in the user interface, which a subset of the keywords that are relevant to the entity based on information in the semantic graph.

5. The method of claim 1 , wherein the message from the client device indicates keywords included in the text of the user interface of the client device in addition to the particular term;

wherein the keywords indicate a time period or geographical location referenced in the text of the user interface; and

wherein the method includes creating an aggregation of data about the particular entity for the time period or geographical location indicated by the keywords, and wherein the response message to the client device includes one or more values determined based on the aggregation.

6. The method of claim 1 , further comprising identifying a user of the client device; and

wherein the response message to the client device has a set of values describing the particular entity, wherein the set of values is customized based on the identified user of the client device.

7. The method of claim 1 , further comprising identifying a user of the client device; and

wherein the response message to the client device has a set of values describing the particular entity, wherein the set of values is customized based on a history of one or more prior interactions of the user of the client device with annotated terms or information cards presented to the user.

8. A system comprising:

one or more computers; and

one or more computer-readable media storing instructions that are operable, when executed by the one or more computers, to cause the one or more computers to perform operations comprising:

storing, by the one or more computers, records that specify a set of terms and records that indicate entities corresponding to the respective terms;

receiving, by the one or more computers, a message from a client device over a communication network, wherein the message is sent in response to a determination that a particular term from the set of terms occurs in text of a user interface of the client device, and wherein the message from the client device indicates the particular term from the set of terms that is determined to occur in the text of the user interface of the client device;

in response to receiving the message from the client device:

using, by the one or more computers, the stored records to identify a particular entity corresponding to the particular term indicated in the message from the client device;

identifying, by the one or more computers, one or more attributes of the particular entity using a semantic graph, wherein identifying the one or more attributes of the particular entity comprises:

determining, using the semantic graph, an entity type of the particular entity;

selecting, from among information card templates for different entity types, an information card template for the determined entity type, wherein the selected information card template specifies a predetermined subset of attributes of entities of the determined entity type; and

identifying the predetermined subset of attributes specified by the selected information card template as the one or more attributes; and

retrieving, by the one or more computers, values for the one or more attributes of the particular entity from a database, including retrieving a value for each of the attributes in the predetermined subset of attributes; and

responding, by the one or more computers, to the message from the client device by sending a response message to the client device over the communication network, wherein the response message identifies the one or more attributes of the particular entity and includes the retrieved values for the one or more attributes of the particular entity, wherein the response message includes the retrieved values for the attributes in the predetermined subset of attributes.

9. The system of claim 8 , wherein sending the response message to the client device comprises providing information card data defining an information card to be presented by the client device in response to user interaction with the particular term, wherein the information card data is provided to the client device over the network before a user of the client device interacts with the particular term in the user interface of the client device.

10. The system of claim 8 , wherein the operations further comprise providing the set of terms to the client device over the communication network; and

wherein receiving the message comprises receiving a message sent by the client device in response to the client device determining that the particular term from the set of terms is included in the text of the user interface of the client device.

11. The system of claim 9 , wherein the message from the client device indicates keywords included in the text of the user interface of the client device in addition to the particular term; and

wherein the operations further comprise selecting, from among keywords in the user interface, which a subset of the keywords that are relevant to the entity based on information in the semantic graph.

12. The system of claim 8 , wherein the message from the client device indicates keywords included in the text of the user interface of the client device in addition to the particular term;

wherein the keywords indicate a time period or geographical location referenced in the text of the user interface; and

wherein the operations further comprise creating an aggregation of data about the particular entity for the time period or geographical location indicated by the keywords, and wherein the response message to the client device includes one or more values determined based on the aggregation.

13. One or more non-transitory computer-readable media storing instructions that are operable, when executed by one or more computers, to cause the one or more computers to perform operations comprising:

storing, by the one or more computers, records that specify a set of terms and records that indicate entities corresponding to the respective terms;

receiving, by the one or more computers, a message from a client device over a communication network, wherein the message is sent in response to a determination that a particular term from the set of terms occurs in text of a user interface of the client device, and wherein the message from the client device indicates the particular term from the set of terms that is determined to occur in the text of the user interface of the client device;

in response to receiving the message from the client device:

using, by the one or more computers, the stored records to identify a particular entity corresponding to the particular term indicated in the message from the client device;

identifying, by the one or more computers, one or more attributes of the particular entity using a semantic graph, wherein identifying the one or more attributes of the particular entity comprises:

determining, using the semantic graph, an entity type of the particular entity;

selecting, from among information card templates for different entity types, an information card template for the determined entity type, wherein the selected information card template specifies a predetermined subset of attributes of entities of the determined entity type; and

identifying the predetermined subset of attributes specified by the selected information card template as the one or more attributes; and

retrieving, by the one or more computers, values for the one or more attributes of the particular entity from a database, including retrieving a value for each of the attributes in the predetermined subset of attributes; and

responding, by the one or more computers, to the message from the client device by sending a response message to the client device over the communication network, wherein the response message identifies the one or more attributes of the particular entity and includes the retrieved values for the one or more attributes of the particular entity, wherein the response message includes the retrieved values for the attributes in the predetermined subset of attributes.

14. The one or more non-transitory computer-readable media of claim 13 , wherein sending the response message to the client device comprises providing information card data defining an information card to be presented by the client device in response to user interaction with the particular term, wherein the information card data is provided to the client device over the network before a user of the client device interacts with the particular term in the user interface of the client device.

15. The method of claim 1 , wherein the set of terms is a set of keywords that has been selected to trigger display of contextual information at one or more client devices; and

wherein the message from the client device is sent while the particular term is displayed in the user interface of the client device, in response to the client device detecting that the particular term is in the user interface and that the particular term is in the set of keywords.

16. The method of claim 1 , wherein the selected information card template specifies layout and formatting for presenting the values of the attributes in the predetermined subset of attributes.

17. The method of claim 1 , wherein the records that indicate the entities corresponding to the respective terms comprise the semantic graph.